My GFR-700hd shuts down with an E01 error message. Any advice Adcom support is not very helpful

SOURCE: Adcom GFR 700 HD Remote code?

If the remote is infrared (IR), you'd need the codes if the Verizon remote is not a 'learning' remote - in other words, facing the two to each other and transmitting/receiving between them. So, assuming the Verizon is not a learning remote, you'd need the IR codes. Some can be found in the back of users manuals but if not, contact the manufacturer and ask for the codes. They'll usually send them to you in a file.

SOURCE: Adcom GFR-700 7.1 Receiver. No output to powered

I am not aware of any known defect, but it might be helpful to know what was done the first time to address this problem. If the audio board was replaced, that basically includes the "crossover" circuitry that feeds the sub out. It is quite possible that that circuit has failed. While unusual for the same problem to recur, it does happen. It would also suggest that rather than the actual problem being solved, perhaps only the resultant symptom was addressed. The bottom line here is that additional research must be done on the circuitry inside the machine.

Keep us posted.

Dan