I think it just started, I have been traveling a lot and my bride uses the battery blower/trimmer more when im gone but im sure she used it some. When i was home for a few days after 6 or so weeks is when i noticed it wouldn't idle.
Only think I'm confused about now is why it was necessary all of a sudden to crank up the idle screw. guess it being like 12 years old i couldn't complain much if it blew completely up tomorrow....
Sounds like your carb is varnished up. I will tell you something that is cheap and easy to try and I have had several times when it fixed the problem when it was just varnish in the carb. Go to your local parts store and get a little pint bottle of Lucas fuel treatment. Dump your old gas/oil mix out and mix up some fresh fuel/oil. Add a little of the Lucas fuel treatment to your jug of fuel and don’t be worried about putting to much in. I would use about 1/5th of the pint bottle in a gallon of fuel and mix it good. Now fill up the tank and fire the motor up, just so you get fuel in the passages of the carb and shut it off. Let it set overnight and see what it does the next day. That has fixed my old FS75 a couple of times and a old MS023 that I used to have after they had set a while and varnished the carb.