I am running software version 7.4.2 on my SPA504G phones. When using the handset, there is alot of bass that is output and makes the party hard to understand. I've attempted using g729, g711, and g722 codecs to alleviate the problem to no avail.
We are also having lots of echo cancellation problems with the SPA504G while using the handset which I believe is linked to the mic input being too "hot". If you turn the volume down on the handset to get rid of the echo you can barely hear the other party.
When using a headset, neither of these issues are present.
Is there anything that can be done about these two issues with the handset?
I have experienced similar problems with the 7965 and 7941 phones as well to a much lesser extent.