Try <Fn> ► and see if that works.

Had or have the same issues with the cursor jumping all over while using a wireless mouse. Thought it could be the touch pad, but couldn't find how to disable the touch pad on our Dell Inspiron without going into the bios, so I covered up the touch pad with a couple of business cards. Worked!! Don't have the issue with the jumping cursor. Don't look great, but it works.