NAD C355BEE Owners - Advice Needed


One of my friend who purchased a used unit few months ago noticed from the user manual that there are links provided together with the amp that shall be connected between the Main-in and Pre-out sockets in normal use. The links were not found in the box when he got the amp.

The question is do the links really need to be connected between these sockets at all times even when they are not in use? How do these links look like? Are these a metal connector or a piece of short wire?

For users of the C355BEE, the user manual page 8 item no. 12(Pre-Out 2) and item no. 13(Main In) states "In normal use, these should be connected to the Main-In sockets/Pre Out 2 Sockets WITH THE LINKS SUPPLIED".

I have sent an email enquiry to NAD but have not got any response from them. Personally I reckon there wouldn't be any issue without the links but just wanted to be sure. Any advice would be helpful. Thanks in advance.
ryder
Here are some options:

http://www.dedicatedaudio.com/inc/sdetail/5274

http://cgi.ebay.com/Audiophile-Grade-Pre-amp-Jumpers-with-Cardas-GRCM-6_W0QQitemZ380024586299QQcmdZViewItem?IMSfp=TL080505199a8044

http://www.needledoctor.com/Audioquest-Preamp-Jumper-Cables

I am personally not crazy about the Audio quest jumpers, but they are better than stock metal bars.
Cardas jumpers may sound better. Music Direct sells Cardas and Audioquest. You could try both, and return one.
Thanks for all responses. I didn't know the jumpers/links need to be in place in order for the amp to work. I need to find out why my friend said there isn't any jumpers provided with the amp since he was listening to it driving the B&W 684 for the past 2 months or so. Thanks for all valuable feedbacks.
The NAD "jumpers" look like a little plastic bar or plate on the back of the amp. Pretty nondescript, don't look at all like wires. Maybe they were confused.
Here is a picture of what they look like on the C355BEE:

http://nadelectronics.com/image.php?x=154