Sorry to hear about your soundboard.
There are a couple of things you could try. I'm assuming you are double winding it, but you might try triple winding.
When I tie strings at the bridge, they all have their ends pointing in the same direction - towards the floor when you're holding the guitar. If you do it that way too, you could try wrapping the E string in the other direction. Put the E string on first, leaving about an inch left over. Then, put on the B string and wrap it over the end of the E string. That should hold it.
Another trick is to take a lighter to the end of the string and melt a little ball on the tip.
I usually just leave LOTS of extra string hanging out for all of the trebles. Like 2 or 3 inches. After they've set for a day or two, I clip them off.
Hope that helps!
"When I became a man I put away childish things, including the fear of childishness and the desire to be very grown up." - C.S. Lewis
Languages: English, German, Classical Guitar.
2003 Sergio Abreu; 1976 Granada