I've never found a pair of earphones that fit my ears with anything but foam. With the Shures I actually found the sound to be better with the foam inserts than the plastic rounded thingies. Tonights flight will be a better test and I've packed the other fittings.

I did take them to the gym this morning and it seems if the earphone cord hangs down I don't have the issue with the sound fading in the right ear. Seems to be one of those curious occurances. I contacted Shure directly just in case its something else.