Well, I was assuming this just happened only once - and in that case I would say it is a random failure inside the mixer. If you say it happened more than once and only with Studio One, it becomes even more of a mystery. I see no way the mixer can see a difference in the software you use on the DAW end..
BTW, there is nowhere else to report.. We're on our own with these mixers, they were discontiunued years ago - ofcourse, for repair you might try to contact Tascam. In this case, if it only happened once, I'd forget about it and move on.