I just got back my Mk18 upper from DD and was putting all the accessories back on when I noticed something odd. The T-1 on that particular rifle was off, and as I was turning it back on I wasn't getting a dot. I could see some illumination, but I didn't get the dot until I cranked it all the way up to 10 (I didn't try any NVG settings with my 14).
So I just assumed the battery must be low and put in a fresh 2032. But it does the same thing - a hot dot at 10 and a bloomed (too bright) dot at 11.
Is that a warranty issue, or could I possibly have a batch of bad/old/weak batteries (I have a bulk pack of Energizer 2032s, showing 2012 mfr date)?