I have found a windscreen that works really well on my GH2's on-board microphone.

Read about it @ my blog. GH2 – Wind Noise No More » FrugalFilmmakers.com (http://frugalfilmmakers.com/2012/06/02/gh2-wind-noise-no-more/)

http://frugalfilmmakers.com/wp-content/uploads/2012/06/GH2-Micover.jpg

Nice.

I have a similar (looking, anyway) muff for my Sony PCM-M10 audio recorder: WindTech MM-50 Mic-Muff Fitted Fur Windscreen MM-50 B&H Photo. I'll have to try it on my GH2. B&H has a bunch of other similar muffs that might work if this one doesn't: windtech mic muff (http://www.bhphotovideo.com/c/search?Ntt=windtech+mic+muff&N=0&InitialSearch=yes).

D

Might check out these folks, closely held family business. I was one of the field testers for their product for the ZoomH1 that led to the WindJacket. It started with me ordering (and paying for) a windmuff for the H1. What they sent me didn't do super well (the H1 mics are awfully sensitive to wind).

So I emailed some suggestions and about a week later a package came in the mail with a note: "Try this and let us know". I sent more suggestions, their design engineer called me and we went over the problem. He had me go back out and test something he thought might help. It did and around a week after that came another package..."Try this one..."

Eventually one worked well, they made some refinements and I have one of their production models for the H1 they call the "WindJacket".

http://www.thewindcutter.com/shop/index.php?main_page=product_info&cPath=1_80&products_id=464

Then I sent my ZoomH2 to them so they could design one around it, it came back less than two weeks later very warmly clad in a WindJacket.

They've got the best products going, good wind protection comes from longer denser fur and these folks don't skimp Their "Stormchaser" models perform topnotch.