The earbud jack on the clamp kit seems very flimsy and floppy. I keep losing connection on the highway and have to reach up and move the plug around to get the sound back. Consider using a more solid jack like the one for the MP3 plug. I plan to use a short (2-3") adaptor cable from the earbud jack to the earbud cable and tape it down to the helmet to reinforce the clamp kit jack.
The earbud kit needs a more substantial jack