Chosen Solution

I plugged my device in and it will either turn on and run super fast or super slow and nowhere in the middle. How can I go about fixing this problem?

Yes, this problem can be fixed. Ways to fix this problem are to check the carbon brushes to see if they are worn out and replace them. If that doesn’t work then check the TRIAC chip to see if it is faulty and replace it. Dremel MultiPro 395 Troubleshooting