Why no sound out of my sony cassette player?

SOURCE: Sony Stereo Cassette Deck TC-WR550Z

Drives belt has become too slack to drive mechanism properly or the drive motor is bad. Have unit serviced for new belt(s)

SOURCE: Sony Dual-Deck Cassette Player/Recorder, doors won't close

Are both sides not staying shut? If it's only one side, look to see if the latch is broken. You should see an arm move when you press down the eject button - while the door is open, press the eject button and see where the arm moves. You should see a hook that catches the door and keeps it closed. It could be broken, or just jammed. Look at the other side of the deck and see it it looks like it's working the same. Unjam the latch arm if it's stuck, or replace it if it's broken.

SOURCE: Sony Handycam CCD-TR64 cassette door won't close

Common problem with this mechanism. In order to fix the problem you will have to replace part called CHASSIS LS. Expensive repair, probably not worth the effort.

Testimonial: "Thanks. We ended up getting a new camcorder. That Handycam was as old as I am (18 years), so it was time for an upgrade anyway."

SOURCE: My sony trv37 cassette door won't close.

If this condition only occurs with as cassette inserted to load this may indicate a condition where the cylinder which holds the video heads is not spinning up when requested by the system control microprocessor.
If the door will not latch closed with/or without a cassette inserted this can indicated a mis-timed condition of the tape loading mechanism.
Try closing the door without a cassette loaded whilst the unit is powered from its AC Adaptor - under certain conditions this may allow the mechanism to reset and may allow the door to then close.
I trust that this information is of assistance! RHN

SOURCE: my Sony DCR-HC62E error code 32:11 cassette door

search youtube for vids on this Sony camcorder C:32:11 problem .... there are several.