Hi , I`m Jack , I will be helping you today Can you please send me a reply when you are ready to proceed ?
What you need is a HDMI audio extractor where the hdmi video signal goes on to the monitor but you can intercept the audio and feed it to your computer speakers , sound bar etc.
Here is an example ; http://www.ebay.co.uk/itm/1080P-HDMI-Extractor-Splitter-HDMI-Digital-to-Analog-3-5mm-Out-Audio-HDMI2HDMI-/151897909458?hash=item235dd228d2:g:WVsAAOSwp5JWWWyU
You can simply search for " HDMI audio extractor " and you will find quite a few on the market and especially ebay .
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