lehner quark cogging

Don't just look to see if they are blown. Look at the tops of the caps. They should be flat. If they are puffed at all, the caps went. Frank at S&T informed me that they did have a shipment of substandard caps a little while back. You may have gotten one, I know that I did.

If it is the caps, you could just replace them yourself. They are not hard to get to.

[zeropointbug]

Yes, they should be flat at the end. Also, if the shrink wrap on them has torn, then that might be a sign that they have overheated as well, and partly damaged, and using it more will eventually kill it.