I have a Redmax weedeater. I've had it for years. Very dependable machine. I have noticed this season that I've been using a lot more string than past years. I have the tap and go head. I don't think I'm doing anything different this year in trimming vs. last year. Is there an adjustment that I can make on the head? Such as how much string is let out per tap? It is actually frustrating me now to have to go back and wind another spool so much more often. Granted I have two spools so my downtime is minimized. However, something just doesn't seem right. Any thoughts?