So I got a new galaxy dx 959 with a 3 wire echo board and open clarifier. After about 5-10 minutes with the radio on the sound gets quiet. The roger beep through the talk back even gets quiet.Sometimes if I tap the radio the sound will get loud again. Seems like after the radio has been on for a while it doesn't get quiet. I was wondering is this normal in the warm up phase? I was thinking it might be a bad solder joint somewhere but I couldn't see any obvious bad solder spots. Anybody experience this before? Any help/ideas would be greatly appreciated! Thanks in advance.