I picked up the IR4 after reading about them here. Over the past month or so I've averaged nights of 75-100+ pics that turned out perfect and also just the opposite showing 100 pics of floating eyeballs on black background.
I think it gets finicky when the battery level dips to 1/2 charge which for mine is right around 500-600 pics depending on temperature. I pop in 4 new C's when it drops 2 bars just to be safe.
That aint too bad to me considering I get my batteries at the Dollar Store. I also haven't had any problems since switching to night mode only instead of 24 hour. Also for night pics get that sucker close to your bait station. I know it says the IR range is something like 30 feet but you'll do alot better keeping it between 6-15 max.
Yes I have been there too and this has all helped to correct the problem of black pics for me.
Maybe that will help you some.