Static on all calls only if dialed from agent interface

[ryanhs]

Agents began comliaing about static on calls and unable to hear the other party today. I assumed it was my network or SIP carrier at first but everything was good. Then I tried dialing directly from the mitel 6865i and I was unable to reproduce the static. I have duplicated this scenario many times at multiple agent stations and it only happens if dial from the vicidial agent screen and never when dialed from the phone. The only difference between the two that I can think of is the utilization of the conference bridge when logged in as an agent. There were no changes on the servers and i am the only admin. The loads on the servers were low and there are plenty of resources. I have rebooted the whole cluster and i'm not sure where to go from there. It might be a long night! Any input would be very helpful! -- Thanks

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VERSION: 2.14-694a
BUILD: 181005-1738

Cluster 1 core + 2 dialers
SuperMicro board and chassis

Core DB+HTTP Server:
openSUSE Leap 42.3
Intel Xeon CPU E5-2620 v4 @ 2.10GHz - 8 core 16 thread
16GB RAM
SSD RAID

Dialer1:
openSUSE Leap 42.3
Asterisk 13.21.1-vici
Intel Xeon CPU E3-1220 v3 @ 3.10GHz - 4 core 4 thread
8GB RAM
HDD RAID

Dialer2:
openSUSE Leap 42.3
Asterisk 13.21.1-vici
Intel Xeon CPU E3-1220 v3 @ 3.10GHz - 4 core 4 thread
8GB RAM
HDD RAID

200 Mb fiber connection
bandwidth.com sip trunks

[carpenox]

how many agents? has that number increased recently?

[ryanhs]

Actually there less than normal because of covid-19. Yesterday there were only 15 agents on that cluster. I also performed the test on both dialers by updating the phone config and changing the server IP in Phones. As I mentioned I duplicated this approx 15 times with various configurations. Mitel 6865i, Yealink T20P and zoiper. Same results each time dialing to two different destination cell phones, very bad static and choppy audio dialing from agent screen and unable to reproduce the problem dialing directly from the phone.

I took a break at 8pm and had dinner, when i returned i tested again and the problem was gone. No difference in quality dialing direct vs agent interface. I tested on the majority of the stations on the call floor and my test envirnment and they were all good. My crontab is esstentially default on both dialers and there aren't any entries for that time period.

Agents have been active for about an hour now and the audio is good.

I'm not a fan of mystery resolutions so I will continue looking at log for that period for any indiciation of what might have happened and what might have solved it.

[carpenox]

I believe there was a level3 router hit with denial of service yesterday which may have been why.