Problem with my ZenDrive2

I'm sure the guy at Hermida is a busy man, and as of yet he has not responded to my Email. Does anyone know of a repair shop (preferably within California) that can look at it? It's developed a low level hum, where as before it was pretty silent. Already tried a different tube. Would leaving it in the trunk of a car on a hot day (106 degrees) been bad for it? It was inside of a briefcase, which should have shielded it from the heat somewhat. None of my other pedals were affected. Thanks in advance.