[Freeswitch-users] FS SIP audio quality?

Comparing FS 1.0.3 audio quality vs * 1.4.2, simple Sip-to-Sip call, or call to VM prompt, or call via gateway to PSTN - FS audio volume level (should I say gain?) seems noticeably lower than on *, this may be a reason that FS audio seems to be subpar, more noise less clear. Test calls made using PCMU codec from X-Lite and Linksys 2002. Is there anything can be tweaked in FS to correct that? Same issue was with 1.0.2.