I have setup my SPA3102 and I can now receive calls from the BT pstn line onto my 3CX system now (ver 6.1.0). The only isue seems to be that the volume seems low when we get the call on the 3CX system. Looking through previous posts it seems that I can change a settings on the SPA3102. Voice - > PSTN Line. Internaltion Control section. SPA To SPTN Gain - currently set to 0 PSTN To SPA Gain - currently set to 0 What are the recommended settings to increase the volume.