30 yards is always my nemesis as well at times for the same reasons. If you have numbered your arrows or have a way to keep track of each one and if there is no consistent one that's doing it then it's hard to pinpoint the problem. I often wondered if I was torquing the bow some or jamming on the trigger but other than that I haven't figured it out. About the only thing that helped this year was cranking my bow up another 1/2 half turn and suddenly I was grouping great out to 40 yards. Not sure if maybe that 30 yards was at a point where the arrow was still bending in some way or what but I seemed to have solved it for at least this season. Watch the next time I shoot though......LOL