Pioneer SX-2300 powers up, but no sound.

An internal fuse may have failed while in storage. Power switch failure is another possibility.

I have a pioneer sx-2300 in my case the symptoms were powers on you could hear relay click but no output and display was spazzing out flicking on and off or partial image on display I found a fried diode in 5 v section of power supply labeled (D607) on pcb. Replaced and that seemed to do the trick. Hope this helps someone. People always say “ fuse “ or “loose connection “ sometimes this is the case but in my experience it’s usally a little more advanced issue than that.

After putting a known good tape in the deck, push play, if the tape doesn't move, try rewind and FF. If nothing happens, the deck has a problem. I assume this is a cassette deck. If so, I always try the thrift stores for a new(used) one. There are good bargains there.

Check an see if you have a and b channel switch for speakers may be on wrong channel

Looking for SX2300 manual.

Buy some electronic contact cleaner in a spray can, attach straw, "unplug receiver" and spray the power button, you may have to remove to be more effective.

Your RCAs should go from the audio out on the TV to the Aux input on the receiver. put the source selector on the Receiver on aux. that should give you sound. Go to the TV menu and verify that it is set to variable output in the audio settings.
Good Luck!

You can buy a replacement unit for about $60.00. Shop time for repair is usually $70-100per hour.

With the power OFF, press and hold the FUNC button until date and time are displayed, use the UP/DN/RT/LT toggle to change values and positions, once time and date are set, turn unit ON.

I’m happy to assist further over the phone at https://www.6ya.com/expert/robert_aad3edb7dfa380b9

a little bit foolish thing: see if you have both the speaker channels (A and B) down. if you have both down it doesn't work - didn't for me.. and obviously make sure you have the right letter down - same outpout as your boxes