Sound card Problem

[bryant]

I have a 5160 Dell that every copule of songs the sound really crackles bad then both speakers have no sound.
If I unplug and reinsert the headphone jack it corrects itself with really clear sound for about two more songs, then the crackling returns.

I have tried different wires, different adaptors to the 1/4" channel inputs, different mixer, etc.

I have used my other backup Dell with the exact same equipment with no problem at all in sound.

Here's the catch, this is really WEIRD:
When I plug the other end of the headphone jack
into the RCA input of the mixer (it is a CD/Tape input),
the sound is strong and clear all night. So it only occurs when I use a 1/4" adaptor into one of the channel inputs.

Remember, I have another Dell that uses this same equipment fine. And I have another identical mixer
that also produces the crackling when the headphones to 1/4" is used with the bad sound card computer.

Can anyone tell me what is happening?