Hi, I have a Grandstream GXW-4104 connected to 4 POTS lines. I created a gateway per the 3CX article "Configuring Grandstream FXO VoIP Gateway" (https://www.3cx.com/voip-gateways/grandstream-fxo/) My firmware is 184.108.40.206. I ran all the AC Impedance Tests in the GXW-4104. The documentation from Grandstream implied any necessary changes would be made automatically by running the Tests. I created Outbound Rules. I made a call and it connected. The person I called had a hard time hearing me. I could hear them just fine. I did this several times to test. All tests had the same results. I could hear them, but they could not hear me very well. I used my cell phone to make an inbound call to the main number that connected to port 1 of the Gateway. The call was sent to the Auto Attendant that I setup. The recording was very choppy. It seemed like little parts of the Audio stream was dropped along the way. Maybe every other packet was dropped (this is just a guess and I'm really just trying to describe what the audio sounded like.) I connect a standard phone to the POTS lines and made outbound calls with good audio quality. I am using 3CX 15.5 Running on Windows 2012 R2 in a VM on a very beefy Dual Xeon server. It is the only VM running on the server. Does anyone have an idea of what may be going wrong or what settings I need to make to the GXW-4104 to get the outbound audio quality acceptable?