Not sure who is respionsible and what to do. We have a test installation of 3cx running with a customer of ours They docall center work, currently running the free license as a trial. In general, things are pretty fine. Sometimes, though, the audio quality SUCKS. Seriously. In every such case we could trace it down to both sides using VOIP, and the other side now having issues "with phone in general" (i.e. they are not aware of a general bad line quality). For a call center this is pretty bad, and I am wondering if anyone else has experienced this and could give some tips about how to handle this? We do not use direct SIP, but a voip provider, naturally, to a phone system - so the call goes 3cx -> voip provider -> pstn -> voip provider -> other side. Any tips how to handle this? I can only assume it is not bandwith and other stuff as ll other connections work with actually very good quality.