The game will automatically force your lock to IR or PD, this is unneccessary and causes a lot of problems. Sometimes even aircraft flying in a straight line and chaffing will cause the lock to “flicker” between IR and PD lock and cancelling the missile spool. Not to mention when you end the lock on IR, it will NOT switch back to PD and making the next lock IR, meaning you can’t spool missile unless you pay attention and switch it back (with a chance for it to just flicker again)
It has made using the sensors on Soviet/Russian aircraft extremely annoying.