1) After much much much farting around, I discovered that this SC-05 I have here will ONLY play back any audio in PURE DIRECT mode AND setting speakers to LARGE.
2) Analog sources when set as above seem to be fine.
3) Digital sources ... are hit or miss. Sometimes I have to turn the unit on/off multiple times before it will start working with digital sources even in PURE DIRECT... when it's not working, it will just play a split second of the source, cut out, play a split second of the source, cut out... repeat forever.
Obviously surround sound, room correction, thx loudness plus, use of subwoofer just about everything is completely broken on this thing. Was told that a whole board needs to be replaced (mainboard???), seems like a classic DSP problem that others have had even from other makes (Onkyo comes up a lot for this...) in that I can sort of get stuff working when bypassing most everything in pure direct mode.
So... big question is, has anybody had this issue and figured out a definitive DIY - I mean, if I knew exactly which board housed all of this dumb stuff that controls the digital processing for sure then I suppose I can put on a brave face and disassemble it and try baking the PCB in an oven for a while to attempt a reflow - if bad solder joints is indeed usually the cause of such nonsense.
For the moment the thing is still pretty useless to me as I can't reliably even get it to spit out two channel audio from any digital input source including HMG. For the longest time I couldn't get any audio out of it at all no matter what until I read some diagnostic steps in the service manual which mentioned setting speakers to large. Even so, I still can't get the headphone jack to output even a peep - I'm guessing headphone output is permanently tied into DSP and pure direct has nothing to do with it.
What a piece of junk, Pioneer is off my list now and to think I always thought they made reliable stuff. I would like to save this thing from becoming just another piece of e-waste but so far everything I've been told is the repair cost would exceed the value of the thing to begin with - what a shame.
I have a Pioneer A-8 under my desk right here that is 30+ friggin' years old and still going strong.
Edit: It seems that with a lot of fiddling like power cycling the receiver multiple times in rapid fire/changing inputs back and forth etc. that it can be coaxed into playing digital sources until it is powered off or the input is changed again. Still will only work in this case in pure direct mode and two channels only - though I suspect if one resorted to using the analog multi-ins from some source that can do all of the decoding itself that might work for surround.
It's a real shame because even temporarily hooked up to a small pair of Polk RTi4 bookshelves and without any EQ at all it sounds great and can really pump. Still, it's a bit of a behemoth just for use as a tempermental stereo power amplifier.
It appears that the board that needs to get replaced to at least resolve some of these issues is the motherboard assembly which the lowest cost I have seen on the net for is direct from pioneer USA for $250+ USD before taxes or shipping costs so really not worth it.
Last edited by BinaryJay; 08-18-2014 at 08:31 AM.