On sound dropouts: I formatted a new card and copied all my music to it, as per Lurker's instructions, but still experienced dropouts. The card I was using (a class 10 Patriot 128GB with about a 48MB/s read rate) must have been too slow. I reformatted the card I had dropouts on previously (a Lexar 128GB card with a 90+MB/s read rate), copied my music over, and have had no dropouts.
Of course, I just added some new music to it, and now the new music drops out.
So possibly try a faster card?
I may post another issue I have soon if I can't find it elsewhere in the forums...