I've come to the conclusion the whole internal microphone problem is caused by the left channel of the microphone being used to cancel out noises being transmitted through the chassis of the laptop. For example: disk and fan vibrations and typing or tapping noises. When the left and right microphone input are balanced not only undesirable noises get canceled out but your voice gets canceled out too.
The SOLUTION is to decrease the left channel a little compared to the right channel (see alsamixer "image" below) . Run 'alsamixer' in a terminal and press F4 and use the arrow keys to move the sliders up and down and move to the next slider. Use Q Z E and C to move only the right or left channel slider up or down. In ubuntu karmic (9.10) you might need to install the 'linux-backports- modules-alsa-karmic-generic' package first, in lucid (10.04) you don't. Alsamixer in lucid (in karmic it might look a little different, like other names for the sliders): ┌──────────────────── AlsaMixer v1.0.22 ────────────────────┐ │ Card: HDA Intel F1: Help │ │ Chip: Intel G45 DEVCTG F2: System information │ │ View: Capture F6: Select sound card │ │ Item: Front Mic Boost Esc: Exit │ │ │ │ ┌──┐ ┌──┐ ┌──┐ │ │ │ │ │ ▒│ │ │ │ │ │ │ │ ▒│ │ │ │ │ │ │ │▒▒│ │ │ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ │ │ │▒▒│ │▒▒│ │ │ └──┘ L└──┘R └──┘ │ │ CAPTURE │ │ 0<>0 80<>100 72<>72 │ │ <Front Mic Boost > Capture Digital │ │ │ └───────────────────────────────────────────────────────────┘ Final thoughts: This bug might not be caused by alsa, I think skype or maybe pulse is to blame. When I did a test recording with 'audacity' the internal microphone worked fine without any adjustments (in lucid). When using other programs (like 'audacity') or when pluging in an external microphone it's pretty annoying that you need to re-balance the left and right channels. -- System Test for microphone failed (ACER Aspire 3810T) https://bugs.launchpad.net/bugs/459982 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
