RESAMPLING ON XL 8bit-12bit

Whenever I resample wavs and stereo sounds, I get a real "crunchy" sound. I would like the bit lowered, but this sound, sounds computerized. Should resampling be done to mono samples? Should more filtering be added? What techniques do you use to resample?

I've noticed that crunchy sound too. And not good crunchy, but that fake plasticy crunch.

And what about the time it takes to resample? I know the quality you choose determines how long the process takes - but it seems to take forever no matter what. Anyone know tricks here?

YES! I thought my MPC had locked up, LOL, but the sound is fake. Sounds like the COSM LP effect on Rolands. IF I knew that I waited that long for nothing, I just could have ran that crap thru my multi-tracker.