Chan_capi Audio Quality Issue

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Asterisk Users 3 Comments

Hi everyone!

I’m installing in our small office a phone system using a Fritz!Card USB
that I found in my attic. I’m using Asterisk 1.8.13, FreePBX 2.11, chan_capi 1.1.6.

Everything works great, I can place outgoing calls, ingoing calls work, internal calls too, voicemail, …

The only problem is the audio quality when using chan_capi to place calls. The remote party can not hear me clearly and from the asterisk side, I hear a clicking noise (I can try to record it if that helps)
repeating at close intervals but only when someone is speaking or when there’s music (basically, when there is no silence).

I’ve skimmed Google for answers and came up with some old posts dating back to 2003/4/6/… speaking about the CAPI_MAX_B3_BLOCK_SIZE value in chan_capi.h. I tried to tweak that value and recompile several times. Each time, I have the same clicking noise but the interval changes. I
can’t get rid of the noise though.

This is currently preventing me from putting my setup in production and I’d really like to find a solution for this.

I’ll be glad to hear any pointers you can throw at me. I can basically try everything as this is not in prod yet.

Thanks a lot in advance!

3 thoughts on - Chan_capi Audio Quality Issue