I was having the same problem.  I've uninstalled and reinstalled sonar.  It didn't change anything.  I also tried a wired mouse and replacing the batteries in my wireless mouse......still no change.  Then I found a thread about changing the text size to the smallest setting.  IT WORKED!  I'm using windows 8 so I right clicked in my desktop and went to resolution, changed it to the smallest setting.  

mark1977
 
I was having the same problem.  I've uninstalled and reinstalled sonar.  It didn't change anything.  I also tried a wired mouse and replacing the batteries in my wireless mouse......still no change.  Then I found a thread about changing the text size to the smallest setting.  IT WORKED!  I'm using windows 8 so I right clicked in my desktop and went to resolution, changed it to the smallest setting.  

This is the only reason an older thread should be bumped.
Great info, thanks for sharing that with us.
 
Regards,
Chuck