Any way to increase sound volume on SIP calls?


We’re not using any Zap devices. Just Polycom 650 IP phones and VoicePulse trunk. During phone calls, the remote party complains that the our voice is too low but we can hear the remote party very well. The problem is not related to phone config (highest mic volume), Internet speed (10Mbps down / 2 Mbps up and QoS giving RTP 72% of the bandwidth), pinging the ITSP revealed no problems. Is there a way to increase the RX voice voulme the same way we do it with Zap?

because all voice are in RTP stream. the asterisk won’t make any change on the RTP stream unless you use Zap.

So the only way is to find the RX gain on the Polycom IP phone.