A:Answer Surround Sound Decoders: The Panasonic DP-UB150P-K UHD Blu-ray player has built-in Dolby Digital and DTS surround processors with support for Dolby Digital Plus, Dolby TrueHD, DTS-HD High Resolution, and DTS-HD Master Audio. Dolby Digital Plus, Dolby TrueHD, and DTS-HD are only output via the player's HDMI output. If you have an AV receiver which decodes Dolby Atmos or DTS:X, you will need to set this UHD Blu-ray player's HDMI output to bitstream.