I did a fair amount of research looking for a solution to what seemed to be a random issue with the VX401. In my case the unit would spontaneously switch between my desired band/display to the 'digital' source. At that point I was usually locked out and a reset would be required. There were a few google hits for this issue, but not many. I thought I'd post in case someone else needs a fix.
I spoke with Clarion (Canada) customer service and they knew of the issue. Unfortunately, this is a hardware issue and my attempts at updating the firmware in hopes of a fix was time wasted. In warranty, send the unit in and following a quick 1-2 day turn around, the unit would be sent back free of charge. Out of warranty the repair and shipping ran me about $100. I sent mine in on a Wednesday and had it back on Friday.
I dealt with Graham Lovell, 905-829-4600 ext7012, firstname.lastname@example.org
. He was extremely helpful and was very willing to get it done ASAP as the problem appeared on Wednesday and we were leaving on Saturday. Got the unit back last Friday afternoon. We departed on time, as planned with our VX401 up and running. No problems from Belleville Ontario to Fenwick Island Deleware.