I've been thinking about your post for a few minutes.
How many sets of batteries are you cycling? And, is it only one set doing this? The possibility exists of a bad battery. Others (and myself included) have reported an even discharge: Both batts being equal voltage when coming out of the mod. Since yours aren't, I'm left wondering a little if its a weak cell and if a different set of batteries might be the answer.
And, worth mentioning - My xtar Wp2 II charges mine to 4.15 and that's exactly what I think should be expected judging by review comments.
I get the exact same with my Pila. I don't drain my VV W batteries all the way but these are my EXACT results so far.
to see if its working try putting your VV down and picking up any other mod including other Reos if you find yourself reaching for the VV within a 4-8 hour period yours is working at its full potential YMMV
