Basic mod for analog out:  We can install a  DC coupled output stage in the two channel outputs of the Oppo that will give you much better sound than any normal opamp output stage.  No coupling caps and only two resistors and a seriously transparent device in series with the signal.  This is the same output stage we use in our Oppo 95 mods.  Here we run it off the stock power supply.  This mod includes damping of the transport, blacking around the laser, damping the CD clamp, damping some parts on the power supply and changing the main input set of diodes in the switching supply. The stock machine has super small dry images that stay within the speakers.  Also the bass sounds anemic and veiled.  Very boring sounding.  Now the sound is way wider with the instruments much larger and real and palpable sounding.  Everything is much more enjoyable....simply a mindblowing difference for $200 plus return shipping. 

Digital out/HDMI out/better picture only mod (for those that let their processor/DAC do all the analog sound processing and conversion):

We remove various distortion producing parts in the AC supply, damp parts in the AC supply, and change the main diodes in the swtiching supply.
Damp the transport in various ways and black all around the laser assembly and underneath the transport cover to reduce laser reflections.  We ground the cover of the transport.
Remove the toslink connector as this is an LED and they mess up the sound (please let us know if you do not want us to remove the toslink connector).
Change the main clock to a super low jitter clock run off our custom cascoded current source shunt regulator.   $350  

I notice a much better picture on standard DVDs not so much on Blue Rays. Sound is much better now.

The above comment was made by a person who got the $350 HDMI out mod on an Oppo 93 .