Something else is turning it back on, somewhere. Check everything that can make this happen.
I have made dozens of DVD’s with subtitles, a few of them with 32 tracks. I’ve never seen this happen before. If you have no success after checking every event or trigger, re-install DVDA.
Jeff
2-Xeon X5680 @ 3.33, EVGA SR-2 Mobo, 48GB DDR3, GTX 580 3072MB, 16TB Attached Storage, Win7, Vegas 11 x64