After cutting several times with my new PCUT, I noticed a few stray cuts in the first 6 inches of the vinyl. I could find no cause for it. It didn't happen after the first 6 inches and didn't happen with the pen using paper. Took me a bit and some careful watching to discover the problem.
If you start the vinyl cutting with less than 5 or 6 inches hanging in front, it will catch on a ledge at the bottom of the fluted aluminum as it rolls down during cutting. Once caught, it bunches up and buckles, raising the vinyl up high enough to hit the raised blade as the head moves across causing the stray cuts.
My simple 'fix'? I used duck tape. Applied a strip of 2 inch standard old duck tape across the bottom of the fluted aluminum and over that ledge. Make sure the top edge of the tape is in the middle of a concave flute of the aluminum or the tape edge will also catch the vinyl. After laying down my strip of tape, I have yet to have a stray cut again.
Oh, and if you're like me and don't remove anything from new equipment, such as stickers and decals, that caution label on the front right side of the fluted aluminum will also catch the vinyl. Either make sure it's pressed down completely or just remove it...