eBay adapters are hit and miss. I bought two and both were wrong and didn't work. for the GoPro Hero 3 and newer, you have to get a 10-pin mini USB adapter. Many of the inexpensive ones are 5-pin and will not work.
The one that @F4celess linked looks to be a 10-pin and should work, but I didn't have luck. I just made my own.
If they are 5 pin, they simply won't. If they are 10 pin I can tell you how. Let me know.I ordered some of the cheap right angle ones from amazon and some resistors. Im trying to figure out how to make the ones that dont turn off the internal mic work correctly. I will let you guys know that experiment turns out in about a week.
Cool. From what I know, a 100k will set it to video output mode and a 300k will set it for audio input. I used a 330k if I remember correctly.they are 10 pin. I measured the resistor value on the official gopro adapter and I have that value here at work to try on the cheap right angle adapters when they come in.