Edit: After not using them for 3 hours it went away. Weird.
evango is fine, I got 2 pairs from him and no problem at all. Could be a manufacturing defect..
It hasn't happened again. I've really been enjoying these MH1. I also find them a lot more comfortable than the V-Sonic, but that's mostly due to the tips. None of the V-Sonic tips fit my ears comfortably. I think I'll get another pair of these Sony's and use those tips on my GR06 since I'm too lazy to replace them everytime I switch IEMs.