It's normal and called "pre-echo". Some folks think it is a sign of a good resolving system to hear this.
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1176734157&openflup&1&4
Dave
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1176734157&openflup&1&4
Dave