First, make sure it is the model with audio RCA outputs on the unit itself. More recent versions had a common cable with the connectors splitting off that cable, those are not the "holy grail" versions. I believe that the "magic" is in all the crappyness in the unit as a whole, warmer tones, less digital sounding,etc. In those threads mentioned, changing the output amps makes it all go away. Once you take out the opamps etc you may as well just play with a better component,because the transport and decoding systems are marginal at best (however the mechanics are very robust, think of all the abuse a PS1 had to endure) I think I bought 5 from thrift shops and mod-ed all of them.(easy, remove some smd components, bypass the output stage (wire the RCA jack directly to the output chip using caps (3.3uf)) Of those five or so, one sounds really good, I even used Auricaps which hang out the back of the unit. It was a fun little project with lots of experimenting (switching power supplies, transports,etc to find the best sounding combo). Honestly its sitting somewhere hardly ever used, but it was fun playing around them.
BTW one of the units I bought at a pawn shop had a return address label in it, which makes me believe it may have belonged to a somewhat popular county singer.
