emusonacid!

Just picked up an alesis io2, just wondering if anybody else is using one on here, I was hoping to send samples back and forth via the spdif digital i/o but the sound quality
goes a bit shit, possibly my computer? anyone any feedback on this device?

never used that interface.. but the first place to start is ensuring that you're devices are synced properly.
either the alesis io or whatever you're sending to (emu sampler?) has to be set to get it's sample rate via spdif.
check your documentation and see if you can set the io to sync externally to the spdif input (or visa versa with whatever device you're using)