[Freeswitch-users] Background noise on SIP 2 SIP calls

Hey everyone! When I place a call from one extension to another (SIP account -> SIP account / both on same FreeSwitch server) there is a LOT of background noise, I guess I would describe it as white noise. On the flip side, when calls are placed through one of our gateways to a landline or mobile the call is crystal clear without any background noise. I've tried different SIP phones in all kinds of ways, from my mobile (using SIP app), from Grandstream ATA, from X-Lite, they all have a lot of background noise on SIP 2 SIP calls. Any suggestions? A setting perhaps?