I too have an AVR 300 with the similar problem. This first happened to me 2 months after I bought one used here on Audiogon. I called ASL, the former distributor for Arcam, and they had ne send the unit to Audiowright in Columbus, OH. In June of 2006 the software was updated and all diodes were replaced. 2 weeks ago the same problem occurred. I spoke with Audiowright in late December and they indicated this was a widespread issue, and in all likelihood all the capacitors and the board for the power supply would likely have to be replaced. If you are not technically savvy enough to do it yourself, the repairs would likely be $400 or more, provided they could get the parts. Since I have never had a problem with equipment failures like this (I still have a working 26 year old Nakamichi tape deck), I wrote to Arcam expressing my displeasure with their product. Earlier this week I heard from Michael Marko, the senior Arcam product manager with American Audio and Video, the current Arcam distributor. Mr. Marko had been with ASL and moved to AAV when Arcam changed distibutors 3 years ago in 2008. In his email to me Mr. Marko admitted there were problems with the AVR 300 power supply (not a smart move from a legal perspective), stated Arcam was working on a repair kit but they were no longer manufacturing complete replacement boards. Moreover he could not guarantee that the repair kit, whenever available, would actualy cure the problem once and for all. Mr. Marko did offer me a discount on buying one of their current products, or the new AVR 400 due out in February or March. Via phone he indicated the discount would be 20% which is "what is in line for what we have done with other customers who have had similar issues."
What Arcam is doing is analagous to a car manufacturer who knows they have a faulty design or part that causes a product to fail, but who refuses to issue a recall or extend warranty coverage due to the faulty design (can you say Ford Pinto anyone). Moreover they will not manufacture replacement parts to repair the isssue, but they will offer you a discount to buy a newer, more expensive version of their product. Does that sound reasonable to anyone with a ounce of functioning grey matter in their cranium?
And lest anyone think the new Arcams are better, the initial AVR 600 and AVR 500 were also made in China. I have spoken to 2 dealers who could not keep working versions of demos in their stores until Arcam switched production from China to Britain 4 months ago. And the new AVR 400 will also be made in China. Good luck with that.
Since the price of the AVR 300 for resale has nosedived since it lacks HDMI and people are aware of the power supply issues, the cost of fixing these may be more that what the receivers are worth. As a physician, I am naturally inclined to avoid lawyers at almost all costs, but I wonder whether a class action suit may not be the only way to get Arcam to actually do the right thing and back up their very expensive products. Your comments or suggestions are welcome.