I have now watched all 6 movies discs with receiver-decoded DTS, and there were no DTS Bombs.
As far as other bombs, given Lucas' (in)famous propensity for altering these movies, it's hard to believe he didn't correct a few things in Return of the Jedi. The effects in the Rancor sequence just do not hold up. The thing and its set look like models, and even with digital compositing, Luke's live action figure does not blend well into it.
Also, the Jabba's Palace Band number has got to go. It was never anything more than an ill-conceived attempt to recapture the lightning-only-strikes-once fun of the Mos Eisley Cantina Band in A New Hope, and it has never worked. There were the original theatrical version and an alternate version released to MTV as a video (!) in 1983, and there is the 1998 special edition version that's on the current BD. It. Is. Awful. They should go back to the original version and prune it severely, leaving just enough to set up the dancer's unfortunate visit to the Rancor pit.
But instead of what would have been those welcome changes, we get blinking Ewoks and Darth Vader's "No!" as he hurls the Emperor down the shaft. I guess this was revisionism on a budget.