I had the displeasure of experiencing the K3 noise blast last night. My ears are still ringing today! One hand ripped the CM-500 phones from my head while the other hit the power button. NR was on with a setting of 1-1. Was on 160m CW at the time.
K3 S/N 1713. Firmware was MCU 3.3, FPF 1.03, DSP 2.26 in main and sub. SubRx was off at the time.
I downloaded and now have MCU 3.76, FPF 1.07, DSP 2.52 in main and sub. I don't know when the problem was supposed to be fixed but hope the new firmware stops the problem.
73,
Joe W8JH
73,
Joe, W8JH
K3s, KPA 500, KAT 500 and KX3 happy user.