Why are you still using standby mode when the world's energy resources are dwindling? If you're not going to use the computer for a while, turn it off. A well maintained PC shouldn't take longer than a minute to boot up.
I fail to see the need for standby mode for modern conscientious computer users.
The background services I refer to are the software processes that music production software runs as. A common tweak in XP (and set as default in Win7) is to set system priority to background services which can help to stabilise a computer used for music.
You must remember the M-Audio 2496 is about 3 years older than the EMU 0404, which is a long time in computer hardware and software development. It's no surprise, then, that the 0404 officially supports standby and the 2496 doesn't. The 2496 is nearly a decade old! A veteran in binary terms.