I can confirm this audio extractor has solved my green screen issues.
Audio output: L/R+SPDIF. Allows the HD Source connected to single HD Display and adds extra one L+R and SPDIF audio out port. Can be connected to the stereo audio output for SPDIF function. One HDMI input convert to one HDMI + Audio (SPDIF + R/L) output.www.ebay.co.uk
Having previously tried a HDMI splitter (one in two out) that did NOT work I was skeptical.
But seems to have solved it for me at least so might be worth a try.
Good luck if you decide to give it a try.
The one you got from Amazon does appear to be the same unit as mine but I suppose there could be a slight spec difference or maybe even a fault with yours.