With the Sony HDR-AS30V in its skeleton frame atop my bike helmet, the audio track for all my rides consists entirely of horrendous wind noise. You can get an idea of the baseline quality from the sound track of a recent Walkway Over The Hudson crossing.
The camera has two mics, although I’m not sure 15 mm of separation really produces meaningful stereo sound:
Note that two of the five pores on each side are closed flat-bottom pits. As with earbud vents , it must be a stylin’ thing.
I added a rounded pad of the same acoustic foam that forms an effective wind noise buffer for the boom mic:
That reduced the overall noise load by buffering direct wind impact, but non-radio conversations remained unintelligible; there’s just too much low-frequency energy.
Surprisingly, closing the mic pores with ordinary adhesive tape didn’t impair the audio in a quiet room:
Out on the road that’s even better than foam over open mic pores; I think it reduces the peak volume enough that the internal compression can regain control. Sticking the foam pad over the tape slightly reduced the noise during high-speed (for me, anyhow) parts of the ride, but didn’t make much difference overall.
The wind noise remains too high for comfort, even if I can now hear cleats clicking into pedals, shifters snapping, and even the horrible background music when I’m stopped next to the Mobil gas station on the corner.