Fired up LT today strong hum , removed all cables ,plugged in only headset hum still there. Hum followed main volume control ,but nothing else. Removed to try in another room with head phones only,hum was gone .Returned to first location ,hum was gone. First time has done this since firmware 2.54.0 -9efa95c. Only diff was removed power. Works fine ,fully connected ,now. Bug?? Might go to 2.53...