TV doesn’t support EAC3 so the audio is transcoded. Are you sure it is direct playing HEVC? Do you have https://tautulli.com/ to monitor the playback.
12-13 21:59:09.690 i: [FF] AudioStream[1-eac3] 6 channels over 1551 (5.1(side)), 48000 Hz, 0,0 padding. ATSC A/52B (AC-3, E-AC-3) - Unknown Profile (audio/eac3), 3,1 Mbps -54 seconden 0,00fps, No Title / Engels (eng), 0 bytes, .
12-13 21:59:09.691 i: [FF] Video decoder doesn't support eac3 (audio/eac3).
12-13 21:59:09.692 i: [FF] Audio decoder doesn't support eac3 (audio/eac3).
12-13 21:59:09.692 i: [FFmpeg] [INFO] : Audio: eac3 ([135][0][0][0] / 0x0087), 48000 Hz, 5.1(side), s16p
12-13 21:59:09.693 i: [FFmpeg] [INFO]
12-13 21:59:09.693 i: [FFmpeg] [INFO] Metadata:
12-13 21:59:09.694 i: [FFmpeg] [INFO] variant_bitrate :
12-13 21:59:09.694 i: [FFmpeg] [INFO] 3105000
12-13 21:59:09.695 i: [FFmpeg] [INFO]
12-13 21:59:09.695 i: [FFmpeg] [INFO] Container metadata entries found: 0.
12-13 21:59:09.696 i: [FFmpeg] [INFO] Stream metadata entries found: 1.
12-13 21:59:09.697 i: [FFmpeg] [INFO] Stream metadata entries found: 2.
12-13 21:59:09.698 i: [FF] Video decoder doesn't support hevc (video/hevc).
