Q: Two audio tracks are being played simultaneously

A:This means that you are using a player that doesn't contain a stream switcher. If you play a file that contains multiple audio/video/subtitle streams, then your player is trying to play them all at once instead of just one of them.

Solutions: Use a player with a built-in stream switcher. For example Media Player Classic.
Use a source filter that contains a built-in stream switcher. For example LAV Splitter or Haali Media Splitter contain that functionality. The K-Lite Codec Pack uses these splitters by default for most formats.

so the problem is, i had been using WMP forever, but last week, it just stopped audio switching. it lists only one audio track but is playing both language tracks at the same time. i tried MPC but there's no movie list like in WMP and other user friendly options...
any ideas?
thanks

MPC actually has more features than WMP. It is just a matter of discovering them. It doesn't have a library feature like WMP, so files need to be opening through Explorer.

But the WMP problem should be fixable. What kind of files give problems?

For example for .mkv you can try this:
Codec Tweak Tool > Media Foundation > disable for .mkv
Then it will start using LAV Splitter.

I also recommend to re-install the codec pack, in case some other software messed with the codecs.

when i rip a movie i have the .avi (video, i think) .idx and .rar (subtitle?) files. all of my multi-language films are effected right now. i have all the splitters chequed off to split audio, does that info help? i will try reinstalling K-lite. thanks for your help

Codec Tweak Tool > Preferred Splitters > AVI > LAV Splitter

had tried b4 asking forum. was able to see 3 corrupted files whilst uninstalling K-lite, tho - that'll do it! well, all reinstalled and running smoothly. thanks for you time and help