I have a Rotel 1080 Power amp, powering Mirage F2 bookshelves/QED Qudos cabling. Pre Amp is also a Rotel, RTC965, recenty upgraded from Rotel RSP960AX.
My problem - with just preamp and amp switched on, i hear a very high pitched noise from the speakers. Not very loud, and does not change with volume. With the previous pre-amp, the sound was only audible with ones ear pressed right up near the speakers. Now it can be heard within a few metres. It has been suggested the problem is one of grounding, however i have added a 'proper' (read: Expensive) isolated power board with no improvement. Switching sources on or off makes no difference except for one exception - if i select a souce connected via optical cable, (Sony MD deck connected via SPDIF) the sound stops! This seems to indicate that the sound only occurs when these is a signal passing through the system....yet, i still here the noise with no sources switched on. Any ideas??????
Baffled & Frustrated!
Matt
