One thing you did not mention: Are you using the radio with the control
head remoted? Or are you using it connected to the radio. Early on, Icom
had a problem with the remote cable picking up rf and shutting the radio
off. I had the problem myself on 2 of them. After consulting AES & Icom, I
was told to put ferrite cores on that cable. So I did. One as close to the
radio under the seat as possible and one near the control head. The problem
went away in both cases. Same is true for the new IC-7000 in the remote
setup.

Ralph W9CAR