Audio tracks won't delete

I followed the manual on this but no go. I have two video layers in Motion 5 but I need to totally delete their accompanying audio tracks. I've unchecked those video tracks, unlocked them as well. But clicking the link icon does nothing for the audio or video layers. I've tried every keystroke I can think of plus double clicking. The link icons won't unlink and I can't delete the audio tracks. any ideas?

You need to do this in the "Audio" section. Make sure the layer isn't locked, then click the link icon to un-link the audio form it's accompanying video portion. Then select that audio layer there in the Audio section, hit the delete key. I've always had to do it in this section.