Years ago, Midway had the "Stainless" finish Aimpoint Micro's (R-1) on sale for a steal, and I picked one up. I painted over the stainless bits, threw an I-O Cover on it, and it has lived on my go-to carbine, set on 7 or 8 brightness most of it's life. I've never shut the sight off since I've owned it. I replace the battery once a year whether it needs it or not.

Recently I adjusted the brightness while shooting, and noticed that setting 9 is now dim. There is still a dot, but it is very dim, as if it is set at the lowest setting. Setting #8 and #10 work fine, as do the rest. Replacing the battery with a fresh one did not help.

I have not contacted Aimpoint yet, and I am not sure how they will react to the sight having been painted (I'm sure they have seen it before). It should be covered under their 10 year warranty, unless they consider the paint a problem. I'll be sending them an e-mail to see what they say.

In the mean time, has anyone seen this issue with a T-1/H-1/R-1 ( or the newer -2 models) before?

Dirty contact?  I'd try "spinning" the rheostat back and forth to try to clear the gunk off.  Works on other knobs I've dealt with.

With such low voltage/current now that you mention it I am surprised there isn't more issue with oxidation.

I did spin the dial a few times, with no discernible change in the dot brightness at 9... I might give it a few more twirls and see what happens.

I had something similar happen (three settings were the same brightness level) on a T1 that I bought second hand. Aimpoint fixed it no problem. 

Any luck on getting your Aimpoint working ? Just found out mine only shows a dot on setting 11 or 12. New battery, same issue.

Not normal.  Let us know what you find

Received my Aimpoint back today. Shipped it out on 10/6, so just at a month.  Paperworks says "replaced board".  No other details. 

Works like new now.

Interesting AP takes care of their customers

Suprised to see a broken aimpoint.

Similar experience though aim point took forever to answer