Trying to disable integrated mic on T42p

[imekul]

The subject pretty much says it all -- I'm trying to find a way to disable the integrated microphone on my T42p. I looked through the BIOS settings, but I wasn't able to find anything relating to the mic.

I know I can mute the mic inside of Windows, but I would like to actually have it disabled, so I can use an external mic/audio input. Right now, the internal mic will be disabled when I have something plugged into the microphone jack, but once that device is unplugged, the mic is live again. And I'd like to prevent this from happening.

Any ideas on how I could do this? Short of keeping something plugged into the mic port or physically disconnecting the integrated microphone, I'm not sure how I can disable the on-board mic but still allow external microphones.

[whizkid]

Welcome to the forum!

AFAIK, the built-in mic and the analog jack use the same circuitry, so you can't disable one without disabling the other. You could use a digital mic with a USB connection, or a CardBus sound card and mute the mic, though, or remove the mic device from the device manager.

[Rick Aguinaldo]

Any ideas on how I could do this? Short of keeping something plugged into the mic port or physically disconnecting the integrated microphone, I'm not sure how I can disable the on-board mic but still allow external microphones.

I am not sure what are you trying to attain. As you have correctly stated, the built-in mike is automatically disconnected once you plug an external source to the mic input. Problem #1 solved. Problem #2: keep the built-in mike out of circuit once you unplug the external source. Why would you want to do that? Does it interfere with the sound functions? If it does then it is faulty. If the mic input circuitry is faulty, then sound problems persist whether using an external or the built-in microphone.

[imekul]

@whizkid -- Thanks for the suggestion.

I am not sure what are you trying to attain. As you have correctly stated, the built-in mike is automatically disconnected once you plug an external source to the mic input. Problem #1 solved. Problem #2: keep the built-in mike out of circuit once you unplug the external source. Why would you want to do that? Does it interfere with the sound functions? If it does then it is faulty. If the mic input circuitry is faulty, then sound problems persist whether using an external or the built-in microphone.

The reason I want to do this is so that I only have a "live" mic when something is physically plugged in. Otherwise, I always have the microphone on and ready to pick up any sound. I'd rather be able to just pull the plug and have the sound cut off, instead of it instantly reverting to the internal mic.

[Rick Aguinaldo]

I still get confused. If you mean the built-in mike is still picking-up unwanted sound while an external mike is plugged, then it is no consequence since its output is disconnected from the mic input of the audio mixer. I would suggest a null plug to mechanically disable it while no external source is plugged to the mic input but the result can be more elegantly attained by digitally switching off the mic circuit from the audio mixer. This you can do also with the external mike if it has no built-in On/Off switch to disable it while not in use.