have to press b twice sometimes.

ive noticed in the last couple of games I've played I had to press b twice to back. I would back and nothing is around me and in a completely safe area and I would back and it would auto cancel a second into it and I have to press b again and then i back. This has happened about 3 or 4 times now in the last few games. I'm not pressing anything and nothing is hitting me and nothing is around me. maybe something you guys can look into.