Loop Regions

Hi,

Practically every time I click anywhere on the time line or indeed anywhere on the screen, a loop region of varying lengths is created - most annoying.

I appreciate there is an old thread on this issue and in response to a similar inquiry, Mike Kujbida suggested enabling 'Options - Prefs - Editing - Collapse loop region when no time selection is present'. I have done this however it does not seem to have any effect.

Could anyone suggest what I might be doing wrong? I'm using Vegas Pro 11.