3.5mm Plug Pinouts

3.5mm Plugs
Discount Hotel Reservations
Get Flash to F... Off
I Hate Frames Club
NetAlarm - Be Alarmed, Not Alert
DRM - Defective by Design
Powered by Linux
Powered by Apache
Uranus Teenysystems
Planet Exploder 5.0
1and1 Banner
The standard 3.5mm audio mini-jack has been expanded into many uses, including audio/video equipment and headphones with microphones. These 3.5mm 4-pole TRS (tip/ring/sleeve) mini-jacks have no standard pinout, so the variations are plentiful. Here are some of the ones I've come across.

AV Plug
Device4321
MonoGroundMono
StereoGroundRightLeft
MP3/Video playersGroundVideoRightLeft
WD TV LiveGroundRightLeftVideo
Camcorder A/VRightGroundVideoLeft
iPod A/VVideoGroundLeftRight
Zune A/VVideoGroundRightLeft
Audigy 7.1 audio port 2Side RightGroundRear RightRear Left
Audigy 7.1 audio port 3Side LeftGroundSubwooferCentre

Some manufacturers just seem to want to make things hard for their customers. Apple, of course, uses any arrangement, so long as it's non-standard. WD's help site tells users that their composite cable is non-standard, but doesn't give details. It also lies by saying "there will be no sound" if you plug an audio output device in directly, whereas you'll actually get left channel audio on the right speaker and hiss (video signal) on the left speaker.