chan_capi echo cancellation break VM recordings


I seem to have a difficulty with * 1.2.29 and chan_capi 1.0.0, regarding
the “echosquelch=1” setting in “capi.conf”. Every time this setting is en-
abled, all calls from PSTN not being answered by a SIP client and there-
fore going to voicemail will record broken audio messages.

Since in a call from PSTN to VM there should only be one way audio, I
cannot see the problem with the echo canceller.

Unfortunately, we have external SIP clients (latency ~30-70ms) as well
and would really like to use the echo canceller, since it greatly helps our
external employees with calls to PSTN.

Perhaps somebody has an idea?