I Have a Teac W525R double auto reverse cassette deck and I cant dub from ;Play (left sd) to Rec. (right sd). What gives? I push rec then play on the other side and the rec stops. Then I tried the other way around. They cancel each other out. Help!

Hi
If you have a dual cassette deck, then one deck will only play cassettes,whilst the other will have a record facility as well.
Basically you need to place the original cassette in the play only deck and the target cassette in the record/play deck.
Start the playback in the play only deck and immediately press the record and play buttons together on the record deck. Some decks have high speed dubbing but this varies so much that you will need to consult your manual for this.
Cheers

There should be a button or switch that will select the recording deck and the dubbing deck. You put a blank tape into the recording deck and the pre-recorded one into the play deck. Pressing the record button on the dubbing deck, on some models should start the play deck running. If not press play on that deck.

Press the Dubbing A to B button. Put your blank tape in deck B. Press REC/PAUSE on deck B. Press Play on deck A

Hi Steve - try this:
Connect amp Tape Playback to deck Line Out.
Connect amp Tape Rec Out to deck Line In.
Play your favourite cassettes.

The leads to the VU meters have shorted out. The fact that it only happens when you push "Record" sounds like part of the mechanism is actually causing the short.

I have not seen those to a large extent due to their value not being worth a repair. I did work on them at Teac though. The capstan motor of the right side deck sound like it is burned out. I have some motors here so it is just a matter of if you want me to work on it or not. I get a lot of units in all the time- I am Skywave Tape Deck Repair in Chicago area.

Receiver Rec Out 1 or 2 to the Teac Recorder Rec (Line)-In;
Receiver Tape In from the Teac Recorder Play (Line)-Out.

http://www.retrevo.com/support/Cambridge-Audio-540A-Amps-manual/id/21962dj979/t/2/

Sometimes you can repair these type of connected strips by melting them back together or on with a soldering iron. Do it in a well ventalated room with a mask and goggles, to prevent the plastic fumes going in your eyes.
The only other way is strong superglue.
You could phone the maker if they still have the parts. But I wouldn't hold out much hope if the model is over 3 to 5 years or more old. Even then it might be cheaper to get the same model off E-Bay.

Better tape decks, like Pioneer, may use a different mechanism for record/play than FF & REW. So it sounds like a belt or mechanical link for the REC/PLAY has failed.

Oh yes, on the TD-WE375 above the left deck also stops playing sound when the right deck is readied for recording.