I try to connect my m2 Soundbar to my TV via the correct HDMI arc port, but it seems to recognize it as a video device instead of as audio. It will occasionally recognize hdmi receiver, but switches back almost immediately to the TV speakers. Any net is enabled, sound is set to pcm. Are there any suggestions apart from using the optical cable? I much prefer not having to use a second remote, and hdmi arc was one of the reasons I bought both pieces.