For some reason, I keep getting this message in the Task Bar area -
"You just plugged a device into the audio jack"
Then id goes away after awhile, but keep coming back and going away?
What could be causing this and How do I fix it?
Thanks for any insights?
charliec
Does your computer have front panel wiring, which runs to FP_Audio ?
FP_Audio is a 2x5 header on the motherboard. At one time, it supported
only AC'97 CODEC standard, and you'd wire up about 7 wires. When Intel
introduced HDAudio, the header pins were redefined. For AC'97, only
five wires are connected (AC'97 case with HDAudio motherboard). The
two return signals (Return_L and Return_R) are not needed, and to
avoid aggravation, I'd pull the pins from the cable assembly so
they can't make contact.
When an HDAudio computer case is connected to an HDAudio motherboard,
then a few more signals get connected. Three of them are "jack sense" related,
and a fourth (PRESENCE#) indicates that jack sensing scheme is being used.
(I've never seen any info on actual usage of those signals, how the
driver detects it, so the four of them are a complete mystery to me.
I know how the SENSE works in that case - it's a four bit ADC that
converts resistor tree switch closures into a four bit jack_sense
bit pattern. But as to how and when the driver uses the info,
whether the driver even cares, I have zero info. Maybe
scouting out some Linux source will tell me more about it...)
There is also an impedance sensing capability in a number of HDAudio
CODECs, which forms an alternate solution to detecting audio plugs.
(The codec can tell when the 10K ohm input of amplified speakers,
is connected to Line_Out, and it's some scheme that senses current flow
out of the port. It's pretty clever, as the ports are AC coupled,
and so the port would have to recognize an AC current flowing out
of the port.)
But I don't recollect seeing much in the way of reports of problems
with that. If you had a "loose ground connection", you'd hear
humming or pops or some other symptoms, which you haven't mentioned.
I doubt the 10K ohm connection from your amplified speakers
is "appearing and disappearing". It's more likely to be
something to do with FP_Audio header and wiring.
I'm thinking
1) You're using front panel headphone and microphone jacks.
2) Computer case cable assembly type is AC'97. It runs from the
front panel headphone and microphone jacks, to the motherboard.
Two of the wires are labeled "Return_L" and "Return_R".
3) The return pins are connected to HDAudio sense pins,
and the driver detects voltage changes on there, as
switch closures on the various jacks. The result is phantom
jack sensing.
If you unplug FP_Audio cable, it'll probably stop.
(As will the function of the headphone and microphone jacks :-( )
Post back with whatever you discover.
Paul
