Heh, likely you're getting incorrect data to begin with.

43,679 is the max number of characters you can  copy/paste from a string in an SSMS grid, a fun old connect item that MS never got around to fixing.

I highly doubt that very specific number is a coincidence, so probably the hex value is just already wrong.

You can work around this by casting the string as XML and then copying it out.

Cheers!