I think 'standard velocity' .22LR ammunition is sub-sonic but since I see both 'standard velocity' and 'sub-sonic' labeled ammunition on the shelves I wonder if there might be a difference.
I had a .22 LR conversion kit from Colt that I used on a 1911 Colt Government Model that was odd - it liked Remington standard velocity best although I seemed to remember the directions advised against it. It was a real jam-o-matic with most ammunition.
I've used both the standard velocity and the sub-sonic marked ammunition in a 10/22 rifle and both ran okay. YMMV.