I have a Brother sewing machine. I kind of agree with most of the previous comments that maybe your "universal" walking foot isn't quite as universal as your friend thought. Find a local shop that sells Brother machines and ask them what types of walking feet attachments will work with your model. If they tell you the one you have should work, the next thing I would check is to see if there are any screws on the walking foot that are not screwed tight. I now have two walking feet for my machine because I thought mine was broken. After spending $50 for a new one, I discovered that the screws on either side of my walking foot weren't very tight which was causing my problems.
So..check with a legit Brother dealer to find out if you have a foot that truly should work on your machine.