Yes...but between 1200 and 1600 I would guess that it'd be pretty marginal.
Check the pins/plug on the battery to make sure they're not pushed back and not making a solid connection when hooked up.
Try running the 1600 one down until it just can't go anymore...do you have another AEG with a weak spring that you can run it on. Run it until it's "dead"...don't go below 8v (measure it with a voltmeter).
Then fully charge it up with a good charger. If I recall correctly, a fully charged 9.6v will be about 12v.
If you still have problems after that...junk the pack or keep it for testing.