I have a lifestyle 28 Series III. I have an optical audio cable connected betwwen my TV and the Lifestyle. When I am on the TV input the sound comes out great on the Bose system and the display says TV Dolby Digital 5.0. When I switch to HDMI1 which has a Firestick, the Lifestyle for to TV PCM 2.0 and I get no sound. What do I need to change?