To check the binding arms theory, lube all the arm joints with silicon spray. That's what a Carefree tech did to help my awning from binding before being all the way out, and when starting in.
If that doesn't fix the problem, use a meter to check the voltage in the wiring where the motor connects.
If the voltage is less than it should be (12v), check for a short, or perhaps water in the connection where the awning wiring plugs into the outside wall of the coach (my connector was badly rusted there due to water intrusion -- had to replace the plug). If the voltage is 12v or very near, I would suspect a faulty motor.
Paul (KE5LXU) ...was fulltimin', now parttimin'
2003 Winnebago Ultimate Advantage 40e
towing 2017 Jeep Grand Cherokee Limited