TOSHIBA SD270EKB - TVBOX to monitor problems..

Hi,

Right, I have all the stuff i need to hook up my DVD player to my PC Monitor, including the TVBOX1440, so i can run the YPrPb connections into the TVBOX from the DVD player and using the VGA to go into my monitor..

The monitor is a: HANNS-G HW191
....and the DVD player is a: TOSHIBA SD270-EKB
...and the connections box as stated is the: TVBOX 1440..

The TVBOX works fine as i can see the menu on the monitor and tweaks the settings etc, so i know the TVBOX works with the screen....

......but i can't get my dvd player to work through it. all i get is the blue screen..

As i said before, the DVD player is connected to the TVBOX via the YPrPb connections - I'm using standard RCA leads for that - it was and old red / white / yellow rca lead, but surely rca IS rca. Do i need specific YPrPb leads?

Anyway, its not working and this has been driving me miss daisy for nearly a week now, lol..

Any ideas on what could be the problem?