While checking out the recent upscales and uploads of ReBoot episodes, there were multiple times that had me thinking "wait, I don't remember it sounding like this". The two episodes that stood out to me were The Quick and Fed and The Crimson Binome, and luckily the episodes I had burned onto DVD-Rs years ago were of YTV broadcasts. I assume the newer variations come from (some of?) the DVD releases, given all stories I've heard about their audio problems. I like the original versions better.
These are just some examples of music differences, and is by no means thoroughly researched or comprehensive. I noticed another difference while clipping The Crimson Binome that I didn't include, and I wouldn't be surprised if more instances exist.
(go to the youtube video for clickable timestamps)
00:00 - Bob BSnPs through the window.
00:18 - Skeleton fight.
01:38 - Running up the tower, no music.
01:54 - Bob BSnPs through the window, music ends differently.
02:14 - Skeleton fight, with completely different music.
03:38 - Running up the tower, now with music.
03:52 - Boarding the Saucy Mare.
04:41 - The music track is used differently, with a pause for Dot's line, and keeps going after Frisket gets filelocked.
05:32 - Business talk, no music.
06:27 - Are you tired of the pirate theme yet?
In 1982, quite by accident, a zookeeper at Izu Shaboten Zoo in Shizuoka Prefecture discovered that capybaras absolutely loved soaking in hot water, and the practice of providing them an onsen, or traditional Japanese hot spring, was born. Source Massimo; video @yu_haradakei.