one of our customers in Germany has a VoIP network consisting of a CUCM 18.104.22.1680-3 cluster and 2 Voice Gateways (Cisco 2811, IOS c2800nm-ipvoicek9-mz.124-15.T6.bin).
As the title already indicates, PSTN users are complaining about low volume on calls with users on this VoIP network.
Cisco suggests the following solution (adjusting input gain and output ettenuation):
Since my experience is limited in the VoIP field, my question is if this solution has any side-effects which one should be concerned about. If its relevant, we also have fax calls across these Voice Gateways. No other PBX is connected.
Here is some of the cofiguration that might be relevant:
no ip address
isdn switch-type primary-net5
isdn timer T310 10000
isdn overlap-receiving T302 6000
isdn incoming-voice voice
isdn number called enbloc 1
isdn outgoing-voice info-transfer-capability 3.1kHz-audio
no cdp enable
controller E1 0/0/0
pri-group timeslots 1-31
voice service voip
no supplementary-service h225-notify cid-update
h225 timeout t302 6
h225 signal overlap
no h225 alt-ep hunt user-busy
call start slow
dial-peer voice 1 pots
tone ringback alert-no-PI
description --------- main dial-peer in+out
progress_ind setup enable 3
progress_ind alert enable 8
incoming called-number .
Would be grateful if anybody has any advice!