[Arny Krueger]

"Mike Rivers" wrote in message

I have a Tosiba NB305 series Netbook computer here
running Windows XP. 'Scu'se me for my simplicity, but
when I'm traveling and need to edit some audio, I just
use the built-in audio hardware and plug headphones into
the jack on the side of the computer.
I usually don't shut down Windows, but rather put it into
hibernation. It uses practically no battery in that mode
and starts up quickly when I want to use it again. But
what I've found is that after a few cycles going in and
out of hibernation, I lose the audio output and have to
restart Windows in order to get it back. Audio programs
don't complain that they can't find a playback device,
the Windows Sound/Audio window shows the correct audio
device, and the mixer doesn't show that it's muted. (yes,
I've tried exercising the Mute button and also checked
for 'reversed' operation).
Does anyone have an educated guess as to what's going on
here? Is there any way I can reset the audio without
restarting Windows? It's not a big deal, I'm just
curious as to why this happens. I suppose it could be a
Toshiba thing, that it somehow disconnects the headphone
output amplifier to save the battery after a certain
length of hibernation time, but I've had the audio work
after several days of hibernation. It seems to go away
after a number (unknown) of hibernation in/out cycles.


The device drivers for all of the peripherals of a PC have entry points that
relate to power management. Whenever the PC changes power state, such as
turn on, turn off, hibernate, goes into suspended animation, various degrees
of sleeping, etc., these entry points are called by Windows. If the code
that backs up these entry points is defective, then symptoms such as the
ones you are experiencing may be observed. You might want to try to update
the device driver for the built-in audio interface on your laptop. Usually,
the chip vendor has the latest-greatest version.