Bugzilla – Bug 12905
Headphone polling creates noise on line-in
Last modified: 2009-09-08 09:26:40 UTC
The enable-disable polling for the headset detect creates a 0.5hz pop (pretty low level), on the line-in. I think we can be smarter about polling the headphone. Use the previous HP detect method until a HP is inserted. Only when it is inserted, then do the off-on trick to determine the HP type. Then more polling is unnecessary.
Fixed in baby-mp r6677. Caleb, can you please test and confirm it works with all headset types.
Headphone detect seems to be reliable, but headset type detection is not. I think you should probably either increase debounce time, or just wait for .5 to 1 second after headset is detected, then do the disable/enable trick to detect type.
I see both a 3-wire detected as 4-wire, and 4-wire detected as 3-wire.
Fixed in baby-mp r6737. The headset type detection has been disabled for now, so we don't detect if the headset has a mic.