Hi All, One of my clients is experiencing an issue where the person calling in still hears the phone ringing - almost looped. This appears to be an issue with the latest firmware 18.104.22.168 (would not recommend upgrading to this). Grand Stream seems to be working on a new firmware, but does anyone have any suggestions on what i can do to get my customer up and running again? Has anyone downgraded firmware on the GXP2100 before, if so can you recommend a stable firmware that works with 3CX V10? Thanks!