Looking for help identifying delay receiver gets when answering a call

My system is local and both phones are local as well. I’m trying to figure out why the person receiving a call can’t hear the audio from the caller for 2 - 3 seconds. I’ve got brand new phones, brand new switches, and a brand new server. Asterisk 19.8.0, FreePBX I have a pcap between the two phones, but I’m not sure what the best way to share it is. I’m looking for suggestions on what I can check.

Either put the .pcap into a .tgz file and attach it to your post using the upload button, or just rename the .pcap to .tgz and upload it (we will rename it back to read it).

Ok thank you. I’ve renamed the extension and attached it. I have just the two phones filtered out. If the full pcap is needed let me know. Also the ping between the computer next to 10.25 and 10.25 is < 1ms.

acsupdated.tgz (961.6 KB)

AFAICT, in frame #24, Astrerisk correctly asked the Fanvil at to send it ulaw audio, but the phone (except for one random packet), didn’t start sending it until frame #249, more than two seconds later. IMO a phone firmware issue is most likely. Possibly, disabling video and/or the unused audio codecs will work around the problem. Or, the phone may be attempting some lookup (DNS, STUN, etc.) that’s not relevant to this call and can be disabled. There may be a firmware update that will help.

If no luck, try to confirm (or refute) this hypothesis by calling from a different brand of phone, or a softphone if you don’t have one.

Thanks for the info. The delay only happens sometimes which makes me think it’s not a firmware issue, but who knows. If I switch it to just ulaw and the issue is gone, then maybe it is a fw issue.

My phones have codec settings under line > codec settings and phone settings > media settings > codec settings. Any idea what the difference is? I’m going to try setting them both to ulaw for all of my phones.

I’ll check into dns and stun. I’m sure stun is off, but never know with dns.

I will test soft phones as well as I don’t have any other hard phones.

After studying the pcap further, seq 0 for each phone starts at time 15.518006 (frame 19) and 16.266553 (frame 105) repectively, however, the one that starts later has a destination unreachable ping. Maybe that failed ping is related?

Any other ideas? Some phones work fine and some phones there is a multi second delay. I’ve removed all but 1 codec on all of the phones. Ping to affected phones is <1s. I have qos enabled on all of the phones and switches and verified they are all being tagged properly.

This make sense to anyone?

Audio delay of 2s for incoming calls - “Answer() before Dial()” fixed it!? - Asterisk / Asterisk SIP - Asterisk Community

Promising update. Factory resetting the phones seems to fix the issue. I’m testing with a Fanvil X6U, X210-V2, and Yealink T28P

When I first set each phone up the first thing I did was upgrade the firmware. Then I restored a generic config onto them and modified it as needed.

Either not factory resetting after the firmware update or the restoring of the config itself is causing this delay. I have a test lab set up with 3 phones that were all showing the delay issue sitting right next to each other on a completely different switch on both FreePBX and 3CX. After a factory reset, BAM, instant connection both ways.

I still need to eliminate restoring the config as the cause of the issue, but this is very promising. Even if I have to set each phone up manually, this is just amazing.

This topic was automatically closed 31 days after the last reply. New replies are no longer allowed.