Have a problem getting the LS1212 brake to stop the slide action. The inner knob on the front no longer controls it. Any ideas?

My 15 year old saw suddenly startes stuttering really bad. To the point of not running. It's such a sharp kick in for half a second then pause 1 sec then again over and over. Almost sounds like the brake is cutting off the saw function. Put in a brand new switch. The brushes are about 5/8 " long . This malfunction seemed to happen all at once. Not little by little. Closest repair shop is an 8 hr. drive and they don't speak english and may have never seen this saw before. Any helo would be appreciated Mike

It appears that there is something wrong with the turn stopper. The saw is stuck at 45 deg (mitre, not bevel). If I release the lock pin, it will rotate very slightly, but then stops within several degrees of movement.

The turn stopper WILL lock the saw; unscrewing it to release will allow ONLY the above movements.

When I look inside the base, I see very slight movement of the turn stopper. My feeling is that the tapping screw (#134 on the exploded parts diagram) may have worked loose, or some other related part has dropped out, or a wood chip may be blocking its release, but I cannot see to be sure. I have tried a mirror and still have difficulty seeing inside to confirm.

Is there a known issue with this saw and, if so, is it something that I can easily access without completely dismantling it?

Or can someone tell me how much movement is needed to release te turn stopper. If I reach in with a piece of wire, I can only jiggle it; it does not move freely on its hinge.

My miter saw brake started acting weird yesterday and by the end of the day was making a banging sound when I let off trigger. It sounds like rocks banging around in the motor. I found a post where someone had a problem like this and they were told either the trigger or brushes needed to be replaced. Has anyone had a similar problem? Is there something specific to look for? I don't want to take it apart without a clue as to what to look for:)
Thanks

I have makita ls1212 miter saw..Does any one know if the controller has anything to do with the electric brake? or what parts do?