I've tested the Olympus 45mm lens on the X5 and got so much wobbling. Do i missing a balancing ring that's not yet to buy in the DJI Store?
Or what's the problem here?

I do not show a balancing ring for the 45 mm on the DJI website. I only see 17 mm and 14-42 mm:

http://store.dji.com/product/zen ... om=related_products

I would suggest putting a weight (like a coin), but I wont suggest it!

I did some research, and found a video on Vimeo that shows a user balancing the 45 mm with a sun shade from Ebay.

Please note I do not have any affiliation with this video.



There is a direct link to Ebay on the video description.

If you watch the video you will see some test footage, and notice the slight wobble (still).

DJI not offering the 45 mm balancing ring on their website makes me think camera cannot handle the lens, and will always produce wobble.

Try the 45mm without actually having the Inspire in flight.  My guess is that you will not have any wobble.  Pick it up and shake it around.   You won't see a wobble.  At least mine doesn't vibrate like that.  It's going to take some experimentation to figure out how best to use the 45mm in flight.  Balancing the lens will help a little.  I have a uv filter and a step up ring attached to get mine balanced.  It may be the wind or a misbalanced prop causing the problem.