I have been using my HD500 for a few years. 2 years ago same problem happened and I sent it to the service. They said the motherboard had to be replaced which was I think they said around 300 bucks.. The unit was 500 bucks that time, so I couldn't justify to pay that much money on a replacement part.
It seems like a very common issue. Can Line 6 take any action on this??
It is really unfair customers pay that much money and then suddenly the processor become useless and no different than $100 pedals...
Or at least is there alternative way to connect HD500 to computer beside using USB?