[steaz]

So I recently (2 weeks ago) bought a pair of Phonak PFEs. I've been absolutely loving them, especially since they are the first phone I've ever paid >$100 for. I've been generally using them during my metro commute to and from work (live in DC) and powering them with my iPhone 4. I've loved the isolation they have been able to provide, especially with the included silicone tips--the comply's just don't fit. Anyway, I've recently started having a strange problem in which I randomly start losing large amounts of volume. It's extremely noticeable, and even when turned up to full volume, it's probably a solid 20 decibels lower than my preferred listening volume. 
 
I can't decide what the problem is--whether it's the IEMs or the phone. Generally, once I come inside and turn off the iPhone for a while, I can return to listening in a few minutes with no problem.
 
It has recently dropped to be very cold on the east coast, and my first thought was that maybe the drivers are affected by the cold? Is this possible? I hope not, because I don't really consider 30 degrees to be extremely cold, and I would hate to have to put these bad boys away all winter. Anybody have any thoughts?

 

[kmhaynes]

Just a guess, but it sounds more like a battery issue on your iPhone.  Once the battery falls below a certain percentage of power, it's possible that it cuts power to "non-essential" apps like the player.  I doubt it is your PFEs -- balanced armature drivers are pretty impervious to external conditions.
 
If you have access to a different music player that you can test the PFEs with for a day.