My Frigiidaire electric dryer is about 5 years old. It's a model LEQ 1442 and it beeps constantly. It's beeps 3 times in succession, then beeps another 3 times, and goes on for 5-10 series in succession. sometimes it stops and then starts beeping again in the similar pattern near the end of the cycle. I've cleaned the lint filter, the vent both at the connection on the back of the dryer and where it connects outside. And even with all this, the beeping continues. Any ideas?