HP lists several troubleshooting steps for your laptop at:
http://h10025.www1.hp.com/ewfrf/wc/document?lc=en&cc=us&docname=c00035555&product=455048&dlc=en&lang=en
You could also try the Windows sound troubleshooter.

Maurice J. Reid wrote:

>I was asked a question by a friend who has an HP ZE5400 laptop Pentium IV. He suddenly completely lost sound. Everything else is working find. He could not give me any more specs than mentioned above. If it was desk top I might have been able to help, but my knowledge of lap tops is limited to which part of the anatomy you place them on. My guess is that his sound card is wasted. I do know that, regarding the inside of a laptop, there are limited repairs that can be done by the user or even a local shop. If there is a relatively simple or inexpensive solution possibility, this is about the best place I know to find out. Thanks in advance,
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