Troubleshooting
Find diagnostic steps for connection, call, audio, messaging and account issues.
Registration & connectivity
Capture a SIP call trace for IllyVoIP Support with Wireshark
Capture one authorized SIP call, inspect its signaling flow in Wireshark and prepare private evidence that IllyVoIP Support can correlate with call reports. →
Capture and inspect an IllyVoIP SIP call with sngrep
Use sngrep on your PBX to collect a focused SIP trace, inspect a call flow and prepare private evidence for IllyVoIP Support. →
Check pfSense NAT when an IllyVoIP phone has missing audio
Distinguish a SIP phone from a hosted PBX, inspect pfSense NAT and test only the source-port or firewall change supported by call evidence. →
Check SIP ALG on TP-Link Deco When Troubleshooting IllyVoIP
Check the SIP ALG setting on supported TP-Link Deco systems, run a controlled before-and-after VoIP test and restore the setting if it does not help. →
Check SIP and RTP firewall ports for an IllyVoIP connection
Check the signaling and media ports used by your IllyVoIP phone or PBX. Build a firewall worksheet from actual endpoints, RTP settings and SIP traces. →
Check the MikroTik SIP helper when IllyVoIP calls fail
Inspect RouterOS SIP helper settings, compare an affected IllyVoIP call and test a reversible change without clearing unrelated connections. →
Collect focused Asterisk logs for an IllyVoIP support case
Check Asterisk logging, capture one failed IllyVoIP call, restore the previous settings and share a reviewed private support excerpt. →
Diagnose DNS lookup problems for an IllyVoIP SIP server
Check SIP hostname resolution from the affected network, interpret A, AAAA and SRV results, and separate DNS failures from registration or audio problems. →
Diagnose IllyVoIP SIP and audio traffic through OPNsense
Trace OPNsense firewall and NAT behavior for an IllyVoIP endpoint, then test a scoped correction without disrupting unrelated connections. →
Diagnose Network unavailable on a Yealink phone used with IllyVoIP
Troubleshoot a Yealink Network unavailable message with link, DHCP, gateway and DNS checks before changing your IllyVoIP SIP credentials. →
Diagnose SIP 403 Forbidden on an IllyVoIP phone or PBX
Separate SIP registration and call rejection, check the correct IllyVoIP identity and collect evidence for a 403 Forbidden response. →
Fix SIP Registration Failed on an IllyVoIP Phone or PBX
Diagnose SIP registration failures step by step: authentication mode, credentials, server, transport, timeouts and the evidence to send to Support. →
Investigate SIP 406 Not Acceptable on an IllyVoIP connection
Investigate SIP 406 Not Acceptable on an IllyVoIP connection. Identify the responding system, inspect Accept headers and distinguish 415 and 488. →
Investigate SIP 408 Request Timeout on an IllyVoIP connection
Separate a SIP 408 response from a local timeout, identify the affected connection and collect the right evidence before changing settings. →
Investigate SIP 488 on an IllyVoIP phone or Asterisk trunk
Investigate SIP 488 using the rejected offer, codec overlap and media-encryption settings instead of assuming every rejection has the same cause. →
Recover IllyVoIP calling on a reset Yealink W70B base
Recover a reset W70B by checking handset pairing, restoring its IllyVoIP SIP account and reviewing incoming and outgoing line assignments. →
Restore a Yealink desk phone’s IllyVoIP service after a factory reset
Restore a reset Yealink SIP desk phone using the correct IllyVoIP line, registration settings and incoming-number route. →
Run the 3CX Firewall Checker and investigate failed tests
Run the 3CX Firewall Checker in a maintenance window, interpret failed tests and verify your IllyVoIP trunk after a focused network correction. →
SIP response codes
Guide to SIP codes and troubleshooting your calls →
Test an IllyVoIP SIP endpoint with OPTIONS and sipsak
Use a bounded SIP OPTIONS check to investigate IllyVoIP signaling reachability, interpret replies and collect a useful support report. →
Test your connection to IllyVoIP
Run IllyVoIP connection checks in the browser or Android app, distinguish interruptions from results, and understand what the test measures. →
Troubleshoot IllyVoIP calls behind a FortiGate firewall
Identify the FortiGate policy, SIP ALG and session-helper behavior affecting an IllyVoIP call, then test one justified change with a rollback plan. →
Troubleshoot IllyVoIP calls behind a SonicWall firewall
Inspect SonicWall SIP transformations, NAT and the matching policy before testing a targeted change for failing IllyVoIP calls. →
What if authentication keeps failing?
Check the SIP username, authentication method, password and server against the selected line. A 401 or 407 challenge can be part of normal authentication; repeated failures need the full sequence and response text to diagnose.
The webphone is offline. What should I check?
Open webphone Settings and review Availability, the selected SIP line and which tab controls the session. Switching Availability off signs the webphone out in every tab until you turn it back on.
Does the connection test measure call quality?
It checks reachability and response time from your browser to IllyVoIP services and regional browser voice edges. It does not measure bandwidth, jitter, packet loss or real call audio.
Where do I get current SIP server settings?
Open SIP Lines and expand Technical endpoints. Match the regional hostname, transport and audio settings to your client. Do not copy addresses or technical prefixes from old screenshots.
How should I interpret a SIP error?
Read the full registration or call sequence. A challenge response can be normal; repeated failures need context. Collect the response text, time and Call ID where available.
Where can I check for a service notice?
Use the external network status page for published notices. A normal status page does not rule out an account-specific, device or local-network problem.
Incoming & outgoing calls
Check incoming-call alerts in the IllyVoIP Windows app
Check incoming IllyVoIP calls on Windows by separating number routing, app readiness, notification banners and ringtone audio. →
Check the destination when your IllyVoIP number does not ring
Check an active number’s saved destination, follow the relevant SIP, queue, forwarding or application route and collect useful support evidence. →
Diagnose unavailable, busy and declined IllyVoIP calls: SIP 480, 486 and 603
Compare unavailable, busy and declined call responses using recipient state, IllyVoIP routing and a focused SIP trace. →
Find disconnected or incomplete steps in a Voice Agent flow
Find missing destinations and incomplete steps in an IllyVoIP Voice Agent flow, preserve working branches and verify the corrected update. →
Find unwanted call forwarding on a Yealink T57W used with IllyVoIP
Inspect always, busy and no-answer forwarding on a Yealink T57W used with IllyVoIP, distinguish server codes, and verify the intended incoming call route. →
Find why an IllyVoIP call recording is unavailable
Check recording eligibility, filters, processing and account access when an IllyVoIP call recording is missing or unavailable. →
Follow an IllyVoIP SIP call from INVITE to hangup
Read a SIP call trace for an IllyVoIP call, separate provisional responses from answer, and identify the leg that ended the conversation. →
Investigate an IllyVoIP SIP call that drops after about 30 seconds
Find the evidence behind an IllyVoIP call disconnecting around 30 seconds, including ACK handling, routing and the observed hangup initiator. →
Investigate P-Asserted-Identity and caller-ID mismatches on an IllyVoIP trunk
Compare P-Asserted-Identity, From and caller-ID policy on an IllyVoIP SIP trunk, identify conflicting headers, and collect a precise sanitized support case. →
Investigate SIP 404 Not Found on an outgoing IllyVoIP call
Trace a SIP 404 to the responding system, inspect the actual dialed address and check PBX number transformations without guessing the cause. →
Investigate SIP 413 Request Entity Too Large on an IllyVoIP call
Investigate SIP 413 on an IllyVoIP trunk using the rejected request, its source and a bounded comparison before changing PBX settings. →
Investigate SIP 487 Request Terminated on an IllyVoIP call
Read SIP 487 alongside CANCEL and call-leg evidence to distinguish canceled attempts, answered branches and genuine calling problems. →
Investigate SIP 500 and 503 responses on an IllyVoIP connection
Investigate SIP 500 and 503 using the failed request, responding hop, call timing and IllyVoIP records without assuming an outage or retrying blindly. →
My SIP phone is registered, but outgoing calls fail
Find why a registered SIP phone or PBX cannot make outgoing calls. Check dial rules, caller ID, account restrictions, routing, capacity and call reports in order. →
Read SIP headers when troubleshooting an IllyVoIP call
Read a sanitized SIP exchange for an IllyVoIP call, distinguish routing and identity fields, and correlate the result with the Portal safely. →
Reject anonymous incoming IllyVoIP calls on a supported Yealink phone
Use local anonymous-call rejection on a documented Yealink SIP-T73U account and test its effect on incoming IllyVoIP calls. →
Trace PRACK and reliable provisional responses on an IllyVoIP SIP call
Trace PRACK and reliable provisional SIP responses on an IllyVoIP call, match RSeq and RAck and collect focused evidence for Support. →
Trace SIP REFER and NOTIFY when an IllyVoIP transfer fails
Trace REFER, NOTIFY and the resulting call leg to diagnose an IllyVoIP transfer, distinguishing request acceptance from the final transfer outcome. →
Trace who cancelled an unanswered IllyVoIP SIP call
Identify the sender of SIP CANCEL on an unanswered IllyVoIP call and distinguish cancellation, rejection and answer-race behavior. →
Troubleshoot incoming IllyVoIP calls on a locked Android phone
Troubleshoot IllyVoIP incoming calls on a locked Android phone by checking the destination, selected SIP line, connection and call permissions. →
Troubleshoot incoming IllyVoIP calls on iPhone
Troubleshoot IllyVoIP incoming calls on iPhone by checking the receiving line, Portal destination, Focus settings and foreground versus locked behavior. →
Turn off Do Not Disturb on a Yealink T54W and check incoming IllyVoIP calls
Disable DND on the correct Yealink T54W line, check ringing and distinguish a local phone setting from an IllyVoIP routing or registration issue. →
My device is registered, but incoming calls do not arrive.
Check the active phone number’s saved routing destination as well as the device identity. Registration and incoming-number routing are separate parts of the call path.
Audio
Check RTP packetization when IllyVoIP audio breaks up
Measure RTP packet spacing and timestamp steps for an IllyVoIP call, distinguish loss from packetization, and test one media change at a time. →
Check RTP payload types against SDP when IllyVoIP audio fails
Compare RTP payload types with the negotiated SDP on each IllyVoIP call leg, separating speech, telephone events and protected media. →
Diagnose an IllyVoIP SDK call with preflight checks and WebRTC statistics
Run IllyVoIP SDK preflight checks and inspect sanitized call statistics while distinguishing browser permissions, signaling and actual media evidence. →
Diagnose choppy IllyVoIP calls: jitter, packet loss and network load
Diagnose choppy IllyVoIP calls, identify congestion and test a measured QoS change without guessing at router settings or audio causes. →
Diagnose missing ringback and early audio on an IllyVoIP SIP call
Distinguish SIP 180, 183 and actual early audio when an IllyVoIP call is silent before answer, without mistaking progress for a final outcome. →
Find the cause of echo during an IllyVoIP call
Locate the source of returned speech during an IllyVoIP call using handset, headset and call-path comparisons before changing audio or network settings. →
Fix Keypad Digits Not Working During a VoIP Call
Fix telephone menus that do not recognize keypad digits on VoIP calls. Check when digits are sent, DTMF settings and each phone or PBX connection. →
Fix One-Way or Missing Audio on SIP Phones and PBXs
Troubleshoot one-way or missing audio on IllyVoIP SIP calls. Check the affected direction, audio devices, media encryption, codecs and NAT settings. →
Test your microphone and speaker inside the IllyVoIP app
Check microphone permission, input level and speaker playback in the IllyVoIP app before diagnosing a calling problem. →
Troubleshoot the webphone
Use the browser phone, test audio and move an idle browser-phone session to the intended tab without confusing session ownership with routing. →
What if a call connects with no audio?
Compare the device’s audio mode with the SIP line setting and check the selected audio devices. For a PBX or SIP phone, have your administrator review the media path and network configuration. Include whether the issue affects one or both directions when asking for help.
A call connects, but audio is missing. Where do I start?
Check the microphone permission, selected input/output devices, volume and mute controls. For an external SIP device, also compare its audio mode with the SIP line settings.
SMS delivery
My SMS is not confirmed as delivered.
Locate it in Message history and review the status, source, timestamp and delivery details before resending. A sent message is not the same as a delivered message, and a delivery report is not a read receipt.
APIs & webhooks
Diagnose cURL timeouts without repeating an IllyVoIP API operation
Measure cURL connection and response timing for the IllyVoIP API, distinguish transport failures from HTTP errors, and reconcile uncertain paid operations. →
Fix cURL certificate-chain errors when connecting to the IllyVoIP API
Diagnose cURL certificate-chain errors for the IllyVoIP API, check CA stores and approved proxy trust, and restore verification without insecure bypasses. →
Handle a Voice API content-review response in your application
Handle a Voice API content-review refusal, retain its review reference and inspect partial action results before deciding what to do next. →
Handle HTTP 429 rate-limit responses from the IllyVoIP API
Handle IllyVoIP HTTP 429 responses with Retry-After, bounded scheduling and shared-worker coordination without confusing throttling with SMS daily limits. →
Recover a lost IllyVoIP API response without duplicating an operation
Recover an uncertain SMS, phone-number order or Voice API request using its original identity and service-specific status checks. →
Resolve Content Security Policy blocks in an IllyVoIP SDK integration
Diagnose CSP violations in an IllyVoIP SDK deployment and allow only the scripts, connections and media your verified integration needs. →
Troubleshoot IllyVoIP API authentication and permission errors
Diagnose IllyVoIP API 401 and 403 responses by checking environment, current credentials, verification and permissions without repeating paid operations. →
Troubleshoot webhook delivery
Investigate IllyVoIP webhook failures, distinguish log reloads from delivery retries and manage endpoint or secret changes. →
My webhook receiver is failing. What should I collect?
Review the delivery log, HTTP response and error. Verify the signature against the raw request body and deduplicate by the body’s event ID. Do not send the signing secret to support.
Account & payments
Check why an IllyVoIP card top-up was declined
Troubleshoot a declined IllyVoIP card top-up, distinguish verification from checkout failures and check payment status before retrying. →
Continue IllyVoIP app sign-in when the browser is already signed into another account
Handle the existing-browser-account message during IllyVoIP app sign-in and choose deliberately between keeping the session and switching accounts. →
Finish an IllyVoIP mobile top-up after returning from checkout
Return from IllyVoIP app checkout, check the original invoice and distinguish pending payment from confirmed balance credit. →
What if a payment is not reflected in my balance?
Check Transactions for the payment record and status. If you need help, send support the payment reference, amount, method and time. Do not include complete card details, passwords or security codes.
How do I ask about a service charge?
Identify the service and the relevant call, message, order or ledger reference. Include the date, timezone and the amount you are asking about. For a call, also note the destination and routing plan so support can review the correct activity.
What should I include in a support ticket?
Describe the expected result and what happened. Include the date, timezone, device or browser version, affected service and a representative Call ID or message reference. Remove passwords and keys from screenshots.
Need a hand?
Open account support for a specific issue, or contact us to discuss your setup.
Contact support →