Can't find an rca audio out on my hitachi hitachi cmp4121hdu. Is there one? or is it just the wired speaker inputs?

Step 1 Select locations for each of the Coby 5.1 speakers. Place the correct channel speakers in the best location possible. For example, a right-rear speaker should not be placed to the front left of the TV.
Step 2 Measure and cut lengths of speaker wire that run from each speaker to the Coby receiver. Include a few extra feet for mistakes. The speaker wire has two color wires, a red (power) and black (ground).
Step 3 Attach the red wire to the positive (+) terminal for each speaker. Attach the black wire to the ground (-) of each speaker.
Step 4 Make sure the receiver is unplugged. Examine the back of the receiver. There are speaker terminals for each of the speakers. Plug each speaker wire into its respective terminal. For example, plug the right-rear speaker into the right-rear terminal. Each terminal is clearly labeled.
Plug RCA cables into the appropriate input ports on the receiver. For example, there are RCA ports for the TV and DVD player. Plug the other ends of the RCA cables into their appropriate devices. For example, the DVD input on the receiver plugs into the audio output port on the DVD player. RCA audio cables are red and white, make sure to match the colors correctly: red with red, white with white.
Items you will need

• Speaker wire
• Wire stripper
• RCA cables

Check the manual. I doubt that the rca audio is for output. More than likely it's the audio input when using composite video.

internal speakers may be switched off, I/O PCB may be defective, also check the voltage from power supply to audio (I/O PCB) to be sure you have the 12-16VDC necessary, if you have it the power supply OK & most likely the I/O PCB. could also be the speakers themselves(not often both go out together, but possible, can be checked with an ohmmeter) Also be sure to check connecting cables & source..ie. cable or satelite box.

Do you hear sound? If not, check the input cable, cable connector etc for possible loose contacts. If these are ok, there is a power supply failure or secondary power failure inside the TV and might require an expert to look in.

Look for blown capacitors in video or ps

Most Cable Boxes have a audio out out via RCA connections. You should be able to run a Audio Cable from them to the AUX input of you receiver and get a better quality sound.
Hope this helps,
Skyassoc

Connect RCA Red-White audio cable to INPUT of DAV-HDX500 and hook it to TV AUDIO OUT pins at back of TV.
Now select INPUT in DAV-HDX500 to get TV sound in Sony system speakers.

Yes, connect RCA stereo cable at TV OUT or MONITOR OUT terminals at back of TV and connect it to receiver input to get TV sound from amplifier speakers.

This one Wire should be for the +. Try connecting the + to the Head Unit and - to a Common Ground. At the Worst, You will Blow the Amp Fuse if not Correct. The Lead from the Head Unit is Only an Off and On from the Ignition. Please Rate My Response! Thanks!

the suggestion to my guess is right,audio input to the line out jack on tv for it too work you would need the head phone jack witch would go in to auido in an split to RCA Audio out (TV) Witch meaning, adapter to convert regular RCA type (red/white) connectors to a standard mini plug (Headphone type) Hope it Works