Atmos depends on three hops: the app must provide an Atmos track, Apple TV must send it unchanged, and the TV/receiver/soundbar must advertise and pass Atmos. Fix the chain in this order.
Quick answer
- Confirm the title has an Atmos track and select it in the app.
- Use certified HDMI 2.1 cables on every hop; avoid splitters while testing.
- Apple TV: Change Format Off (Dolby MAT), Match Dynamic Range/Frame Rate On, Audio Mode Auto.
- TV: eARC On, Digital Audio Pass-through/Bitstream. Receiver/Soundbar: input mode Auto/Direct, HDMI Out Enhanced/8K.
Symptoms
- Atmos badge shows but the bar/receiver reports PCM or Dolby Audio.
- Audio drops when switching apps or waking devices.
- Works direct to TV but fails through receiver/switch.
Quick checks
- Plug Apple TV into the TVΓÇÖs 4K/120/eARC port with a certified cable.
- Enable eARC and disable TV speakers; set Digital Audio to Pass-through.
- Restart TV → receiver/soundbar → Apple TV to rebuild the eARC handshake.
- Update firmware on all devices; reinstall failing apps.
Step-by-step fix
- Verify cabling and ports – Apple TV → TV 4K/eARC port using a certified cable. Recommended: Certified Ultra High Speed HDMI cable (paid link).
- Configure Apple TV audio – Settings → Video and Audio: Change Format Off, Audio Mode Auto. Leave Atmos on; restart after changes.
- TV eARC setup ΓÇô Turn on eARC, set Digital Audio to Pass-through/Bitstream, and avoid PCM-only modes. Disable quick-start while testing.
- Receiver/soundbar alignment ΓÇô HDMI Out Enhanced/8K, input mode Auto/Direct, no upmixers during testing. For bars, use the eARC port only.
- Test with known Atmos content ΓÇô Use Apple TV+ or Disney+ Atmos titles and watch the AVR/soundbar display as playback starts.
If Atmos is still missing
- Try Dolby Digital 5.1 temporarily; if stable, the link is marginalΓÇöreplace cables/ports.
- Bypass the receiver: Apple TV → TV → eARC → soundbar. If Atmos returns, focus on the receiver’s HDMI board or cabling.
- Turn off CEC auto-switching that may change inputs mid-playback.
- Run Apple TV Check HDMI Connection to confirm the TV still reports Atmos capability.
FAQ
Do I need eARC for Atmos? eARC is best for lossless/TrueHD Atmos from apps; ARC can carry DD+ Atmos but is less reliable.
Why does Atmos vanish after sleep? Quick-start modes can drop the eARC link. Power-cycle in order or disable quick-start features.
Can one bad cable break Atmos? Yes. A marginal HDMI link can drop the eARC channel even if video looks fine. Use certified cables end to end.
Is Dolby MAT the right format? Yes. With Change Format Off, Apple TV outputs Atmos as Dolby MAT/PCM, which most TVs and AVRs expect.