Drives me mad how much places like currys charge for a flipping optical cable. Here is one I found pretty cheap from Play.com. As always with Play, free delivery.
High Performance Fiber Optical Monster Standard LightSpeed Audio Cable to Maxmimize the Performance of Today's Digital Components
For use with DVD, CD, Mini Disc and other Dolby Digital audio applications
Advanced technologies provide enhanced clarity and dynamic range over entry-level optical cables
Specially-polished Toslink connector minimizes signal loss and improves data bit transfer