Hi Ivy,

Have you tried a 'soft' reset on your phone?

If that doesn't work try a 'hard' reset. Be aware that a hard reset will erase all your downloaded apps and user data and restore your phone to a factory default condition. It will be like when you first bought it.

If you wish to do this back up you phone first. Then do a hard reset. Then restore your phone from the backup you made. Just take care that if it was a downloaded app that was causing the problem, by restoring it with your backup you will probably re- introduce the problem again.

The above information is on the basis that your phone has a software problem and that I haven't misinterpreted your question and that the Volume down key is literally stuck in the operated position.

Here is a link that shows what to do.

http://lumiaconversationsuk.microsoft.co...

Hopefully this is of some help.