It really depends on which you are considering. You can find subsonic .22 in the 375 fps range and up. So, it is a hit and miss depending on the particular firearm in question and the particular ammo.
None of my 10/22s will cycle the lower fps stuff; I shoot a lot of it, just manually rack the bolt. I personally like the CCI CB longs at 710 fps. Quieter than many pellet guns. Aquila Super Colibri is just listening to the firing pin hit the case when fired in a rifle.
In a pistol, again depends on the load and particular pistol sample; not nearly as quiet, therefore I don't bother with subsonic in .22 pistols.