BB Psi 16, sand mode.... never slow down....Had the same issue in by BS BB on the beach. Have the stock Michelin tires and was in sand mode. I got stuck more then once. I aired down after the first time and it was only when I had to stop is when I got stuck.
The problem also was that it didn't feel like 4wd when in sand mode. My back tires wouldn't even spin when stuck. Is there something I'm missing here?
Keep a recovery board handy, and a shovel just in case.