An excellent product, does exactly what it is supposed to do hence the 5 stars. However, a tip for those of you wanting to route two different sound sources to a single sound system, rather than one sound source to two seperate amps: check on the back of your two devices that the optical out socket stops glowing red when the device is swiched off or on stand-by.
Example: I bought this to route sound both from my PS3 and from my WD HDTV file streamer which reads video files from a hard-drive. The PS3's optical out stops glowing red on stand-by, so it doesn't interfere with the WD HDTV as long as I swich it to stand-by while the WD HDTV is playing. However the WD HDTV device's optical out socket continues to glow red even when on stand-by, so I can only hear the PS3's sound if I switch the WD HDTV off at the power source.
This is still better than an optical SWITCHER as that would be MUCH bigger (the company sent me that first as a mistake - replaced it very fast without fuss - it was as big as my hand, this is only a little larger than a fizzy drink bottle top) and would require me to get out of my seat EVERY TIME to twist the chunky dial!