Seems very strange - I have always had good service from them.
Have you tried to email? Try some of the address below (or just email them all!):
[email=info@xlnaudio.com">
info@xlnaudio.com[link=mailto:shoporder@xlnaudio.com]shoporder@xlnaudio.com[/link]
<a href="mailto:support@xlnaudio.com]support@xlnaudio.com[/email]
Hope you get sorted soon
Nigel