New question that hopefully someone can shed some light on...
A few weeks ago, I got the dreaded blinking red standby light on my SR7002 - dead power supply
Tried a reset, no luck - took it to the local Australian importer who has a service department. They were very efficient and reasonably priced and "fixed it". But now that I've got it home and reconnected everything I note an annoying "hum" through all channels, from all inputs, that is directly relative to the set volume. Watching TV or movie is bearable, but listening to music (which used to sound wonderful!) is disappointing, particularly during quieter moments, when the hum is much more noticeable. I've returned it to the service department, suggested whatever resistors or diodes they replaced may be slightly off spec, but their first reaction was one of genuine surprise.