OK, here's another build to play with...
Drop that .bin over the top of Warmtoe's last release, and it should be good to go.
Only five changes worth mentioning, most of which aren't that important...
1 - Palettes are now double-buffered. That gets rid of all of the palette tearing effects, or weird blocks of colour on screen when a game was supposed to change the palette mid frame.
2 - Sound channels are now properly synchronised. They were very slightly out of sync before - the right channel was a few samples behind the left. Should result in a slight increase in sound quality. This was needed because the mono output sounded terrible without it (see below)
3 - For those of us who still have to put up with a mono TV, there is now a mono sound output mode. Don't get too excited - it doesn't speed things up, because it's still stereo. It just gets the sound hardware to do a mono mix, rather than a stereo one. It's enabled from the Dreamcast's BIOS (set the sound mode to mono). If you have a mono TV and some sounds were missing (like every other ring "ding" noise in Sonic), check this setting and try with this version.
4 - The sound looping bit from the menu has gone (I never noticed it because it was only the right channel, and I have a mono TV), as has the momentary blip of audio when you start the second (or later) game.
5 - SRAM support has been hooked up. Only works with C68k, and has only been tested with Sonic 3. Seems to work pretty well though - the SRAM save for Sonic 3 takes up a single block, and it still has about 200 bytes free in that block out of 512 total. Loads from and saves to the first VMU only. Error handling is crap, so it might occasionally destroy a save file. The saves from all your other games should be safe though.
No icons though. If anyone wants to draw some (32x32 pixels, 16 colours), feel free. A different one for each game that supports SRAM would be pretty cool. Eyecatch images (the little pictures that appear on the BIOS VMU manager when you have a file selected) might be cool too - they're 72x56 pixels, and can either be 16 color (adds 4 blocks), 256 color (9 blocks), or true colour (16 blocks). Considering their size, I'd probably make them optional.