09-12-2016 12:47 PM
@russelld23113 - I don't believe the external mics will work on the HERO+. They will work on the HERO4, HERO3, and HERO3+.
The waterproof door is going to limit the audio quality some. If you're not doing something where the camera needs to be waterproof, using an open backdoor or The Frame (http://shop.gopro.com/accessories-2/the-frame/ANDFR-302.html) will allow the audio to get directly to the mics.