Can't play audio of video from WD NAS using WD TV Live

I have a WD TV Live media player and have been using it with an external hard drive to play .MKV files, both DVD and Bluray, and music files, with no issues. I have also used the media player to access Netflix by using a homeplug and this has worked faultlessly. I have now bought a WD Live 2 TB NAS drive. I have connected one to the other and all seemed fine as I can see both video and audio files on media player (I have disconnected external hard drive) but when selected neither the audio of video files play and all I get is the circular arrow going around i.e. just seems to be constantly clocking. When I play music files on PC from NAS drive I have no issue. Any help would be much appreciated. Thanks

How are you come connecting to the nas, via media server or network shares?

What WD player do you have, model number?

Hi, appreciate the response. I am connecting to the NAS using a WD TV Live Streaming Media Player. Model C3H. I connect the media player to the NAS via homeplug connecting through a BT homehub. Hope that sufficiently answers your questions.