Roomba 415 bumps into something 3 time, stops

Question

After it stops it peeps eh oh 2 times. If I'm quick enough and move the roomba it continues until it hits the next wall and stops again
I cleaned it, blow all the dust out with blow-dryer and hit the front couple of times also. Nothing seems to work. Now it just goes back and forth in a "seeking way" 3 times and turns around and does it again.
Hope you can help me, this is my 3rd roomba, I love them (when they work but all 3 have not survived more then a year).
Txs