My Ridgid spindle sander started acting up. It seems to take a lot less pressure to bind it up and then it won't restart the sander. I get a buzz, and it might go with a little help, go by itself, or just buzz and do nothing. When that happens there is a burning smell. Any ideas besides the motor being shot? It's a good 2-3 years old and has been a great tool. Just started this tonite.