Seems more than a chain issue. What type of sprocket guards ?Tuck n run chain and rear gears 2 piece and std teeth not skip.
Yes rolling backwards slowly it will jump out of the sprocket as I roll it more settles down in.
Every 2 rotations on the driver it jumps.
Funny thing is I had a new chain 3 races old, used my spare new chain and still in a bind! Haha ! A bind!