Hi. I posted this somwhere else before. You should try the tips from The Koss Plug earphones. For me they work better than Shure olives and anything else I tried until now. And they are really cheap! I bougt a pack with 3 pairs for 15 USD
Don't laugh, but I found the best tips that work for me came from the Sennheiser CX range. My CX300 and CX400 tips fit perfectly and give me the best sound out of the UE's. I've tried Comply T500's and I still felt the sound muffled ( could be my ears ), so if you've got a pair of creative ep630, or anything from the sennheiser cx range and nothing else has worked, then give those tips a try.