I tried one of the cheaper Semsons adapters first and was upset when I got it and it didn't work with my Mogul. Silly me didn't check here to see if it was a known issue, so I bought a HTC official Multifunction adapter
http://www.htcdepot.com/htc-multifun...73A75A4401.htm . You can imagine how ratted off I was when that didn't work either.
I just did the "pin" trick on the Semsons adapter and it works great! I'm charging my phone and listening to Pandora right now. I figure I'll try the same thing with the HTC adapter when I get home.
One little gripe I have is that if you bump the adapter and it moves, it still either tries calling the last dialed number or start voicedial. I can handle that though and suspect it wont happen as much with the HTC adaptor since that fits much more snug.