Applies to: Consumer return-channel education; exact Sony XR-55A80J and Sonos documentary examples linked below. These combine endpoint documentation, not a maker-validated full-system test.
- video
- External source → ordinary TV HDMI input; or source → soundbar/receiver HDMI IN → TV HDMI input.
- data
- No USB keyboard/data path is established by ARC/eARC.
- power
- TV, source and audio device require their own documented supplies.
- audio
- TV apps / HDMI input → TV ARC/eARC output role → soundbar TV audio input role. Optical: TV optical OUT → supported optical IN/adapter.
What the path requires
- Use actual labeled return-channel ports, not any HDMI socket.
- Select audio-system output and appropriate CEC/eARC settings in the exact manuals.
- Match source format, passthrough capability and decoder; use specified cable class including Ethernet where the manufacturer requires it.
ARC and eARC carry different supported cases
Sonos lists Dolby Digital Plus/Atmos for its named Arc/Beam Gen2 cohort, with TrueHD and multichannel PCM requiring eARC. Those product conditions are not a universal codec table for every HDMI connector.
Supported home theater audio formatsOptical is a deliberate fallback
Sonos supports its optical adapter path for specified products, with format and TV-control limits. Do not expect HDMI-CEC or Atmos from an optical cable. Distinguish this consumer S/PDIF use from an ADAT optical input.
TV requirements for Sonos home theater speakersPassthrough and decoding are separate
A TV may decode a format for its own speakers while lacking the required external passthrough mode. Choose a known supported stereo PCM baseline when investigating silence; preserve the original format and settings for comparison. The exact US XR-55A80J manual listing links the cited Help Guide; confirm current on-device menus after software updates.
Television Help Guide — Adjusting an audio systemYour next useful observation
Read the audio device’s reported incoming format, not only the content’s Atmos badge.
Keep these limits
- No universal codec/channel or ARC-version promise.
Source documents, revisions and inspection methods
XR-55A80J Specifications
Sony · 2021 model; live revision unavailable
Connectivity: HDMI ARC/eARC, digital audio output; sound processing
Inspected 2026-10-23 by public_page. Primary HTML body or primary indexed specifications inspected; AI-assisted source reading, no independent human review or hardware validation.
Exact TV has return-channel and digital-audio interfaces; not proof of every app/format.
Read the original sourceTelevision Help Guide — Connecting an audio system
Sony · Live Help Guide identifier iusltn1/v1; revision unavailable
HDMI eARC; ARC; Digital optical
Inspected 2026-10-23 by public_page. Primary HTML body or primary indexed specifications inspected; AI-assisted source reading, no independent human review or hardware validation.
Source-scoped Sony TV procedure; exact region/model menu applicability must be checked against TV Help Guide. Exact US XR-55A80J association verified by live manufacturer listing; see S1262.
Read the original sourceTelevision Help Guide — Adjusting an audio system
Sony · Live Help Guide identifier iusltn1/v1; revision unavailable
Digital audio out; PCM; eARC passthrough note
Inspected 2026-10-23 by public_page. Primary HTML body or primary indexed specifications inspected; AI-assisted source reading, no independent human review or hardware validation.
Source-scoped Sony TV audio settings; no format conversion promise. Exact US XR-55A80J association verified by live manufacturer listing; see S1262.
Read the original sourceSupported home theater audio formats
Sonos · Live revision unavailable
All home theater products; Arc/Beam Gen2 eARC-only formats
Inspected 2026-10-23 by public_page. Primary HTML body or primary indexed specifications inspected; AI-assisted source reading, no independent human review or hardware validation.
Sonos format decoding and eARC requirements.
Read the original sourceTV requirements for Sonos home theater speakers
Sonos · Live revision unavailable
TV requirements; Dolby Atmos; surround sound
Inspected 2026-10-23 by public_page. Primary HTML body or primary indexed specifications inspected; AI-assisted source reading, no independent human review or hardware validation.
Optical vs ARC/eARC, no optical CEC and product-format qualifications.
Read the original sourceManuals for XR-55A80J — Sony USA
Sony · Help Guide listing released 2025-06-25
Manuals & Warranty → English → Help Guide (Web manual)
Inspected 2026-10-23 by public_page. Live Chrome read-only accessibility tree and exact Help Guide anchor href inspected through CUA; web fetch had timed out; AI-assisted source reading, no independent human review or hardware validation.
Exact US XR-55A80J manual listing links to iusltn1/v1/en-003 Help Guide. Regional applicability binding only, not combined-system test.
Read the original sourceSource-documented education. Hardware behavior and independent human review have not been performed for these examples.