Right Earbud Goes Silent -

Ugh - this is so disappointing and frustrating. 

I've had my Vista's for maybe 3 months now - quite expensive as well.  Twice now while in the middle of a run my right earbud just decides to go quiet, down to perhaps 10% of its volume.

These are supposed to be waterproof - sweat-proof even more so.

Do you know how upsetting it is to be shaking an earbud while running in attempts to get sound working again, only to have to finish your run with one working earbud? 

The only thing that seems to fix this is blasting the earbud on full volume once I get home. 

The 1st time it took 30 mins, the 2nd time it took 90mins...  How long will it take the next time?