I bought the USB audio adapter for use with my Pi: http://www.adafruit.com/products/1475
[I'm mostly interested in audio input, which works at least through alsamixer (monitoring input on output).]
But I've noticed that when I use my old iPhone earbuds plugged into the adapter, they get hot. Not burning hot, but definitely a distinct warm sensation in my ears that makes me want to unplug them before they are permanently damaged.
It makes me think that the adapter is dumping a DC bias through the earbuds. Sure enough, my multimeter reads a steady current of 46-49 mA going into the earbuds, and a DC bias of about 2.2 V across the output. That would give a steady dissipation of about 100 mW in each earphone.
Anyone else noticed this?
DAn.
USB Audio Adapter -> Hot Earbuds!
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Re: USB Audio Adapter -> Hot Earbuds!
Thats unusual, we haven't seen this issue before. email support@adafruit with a link to this thread to get a new one in case its a one-off problem!
- whitebabylon
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Re: USB Audio Adapter -> Hot Earbuds!
I bought a USB audio thing off amazon and just got it. I noticed the same thing about my ear buds getting hot. Well that's my two cents.
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Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
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