I am afraid not. Need to go past the point where the sound of the text that has got ahead of it self then rewind to just before and it usually rights itself. Sometimes it is so bad that it just cannot be corrected. I am thinking of replacng it with a newer freeview model but worry that this is a common problem.
Yes, it's VERY annoying. It happened on our 9200, it happens on our HDR-FOXes, and happens on our Freesat 1010. I don't know if it's Humax specifically or a general dodgyness in the subtitling system. I usually do a back skip (15s) but it sometimes needs a bit of judgement to avoid it doing it again if you go back too far - it seems to happen when there is a long speechless section but the subtitles carry on, so ideally the skip needs to land just before the speech begins.
It does seem less of a problem on HD, but that's not much help really as the places I really need subtitles are on 5USA and the like.