New to the forum. 1985 Mercedes Becker 612, I just replaced the tape belts as well as the two pinch roller idlers. These parts were broken from the time I got the car. The tape drive now runs, the play, FF, RW, side switch, eject all work correctly. The radio also plays correctly from both speakers. However, now when I insert a tape, I get only a very faint sound from the speakers when the volume is at maximum. Both sides of the tape play the same way, as do multiple different cassettes. There is no wobble or other unusual sound, just extremely faint volume. Anyone have any experience with the Becker 612 tape function? Thanks!