Just wanting to understand....
Compaq Presario 5310 running Windows XP Pro. I have a Memorex external DVD player PLUGGED in to a USB port and ALSO an internal CD-RW without the analog audio wired to the motherboard. Both devices will play using either Real Player or Windows Media player, but will only run sound to the headphone jack on the back of the computer. The headphone jack on each device would be a much more convienient point of access for my headphones.
INTEL 82801BA/BAM AC'97 Audio Controller is running the multimedia output.
I could run down to RADIO Shack or anywhere and buy a 6 foot extension to pipe the audio from the back of the computer, but that is admitting defeat. Guess I'm half stubborn and half wanting to learn.
What do I need to modify to get the headphone jack delivering audio output on the external DVD player or the internal CD-RW?

Thanks to the experts for sharing what they've learned.

What happens if you plug into the jacks on the drives? Does it mute the sound through the speakers? How is sound/sound card configured in Control Panel?With my headphones plugged into the drives the audio is still coming to the jack on the back of the computer, as verified with a second set of headphones singing away from the back of the computer while the first pair is dead at the CD jack.

Which tab in Control Panel specifically would I be checking to answer the config question? Sounds and Multimedia/Audio and also on the Hardware Tab?Audio tab of Sound and Audio Device Properties shows that Intel Integrated Audio is running the show.

Under Sound and Audio Hardware tab I have the Intel 82801 BA as mentioned before and three other CODECs listed

Audio Codecs,
Legacy Audio Drivers and
Media Control Devices
all list Manufacturer (Standard System Device) and Location Unknown. As a check I disabled the Intel driver and then neither Real Player or Windows Media Player would operate. With Intel 82801 enabled I have audio output from the back of the computer.

Stupid suggestion, but i've overlooked more obvious things in my worst moments:

Have you adjusted the volume on the external devices? Many of them have a button or dial of some type for this purpose.

DocI've done everything I can think of at the CD-RW, including the volume dial. I read on another post that the audio cable has to run from the soundcard to the drive so I check that too, and it's fine. That didn't really make much sense though considering that the external drive doesn't have such a cable, just the USB. I wonder if this is something handled by the player software so only really old versions of WinPlayer will even let the audio come out someplace other than the computer headphone jack.Are you trying to play a music CD that you burned or one you purchased?

Purchased. The CD-RW functions properly on my backup machine. On my backup the audio comes out of the computer speaker AND the CD-RW headphone jack simultaneously. Muting the speaker via the volume control on the screen does not affect the drive volume. Only the dial on the drive changes that. On my backup, things work as I expect they would.
It appears that the Presario motherboard is directing audio to the rear jack from the digital info coming in to the motherboard from the ribbon cable. What interrupt, SETTING, etc. would enable the motherboard to tell both an internal and external drive to disable the headphone jack of the drive?

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...It appears that the Presario motherboard is directing audio to the rear jack from the digital info coming in to the motherboard from the ribbon cable. What interrupt, setting, etc. would enable the motherboard to tell both an internal and external drive to disable the headphone jack of the drive?