Fix Apple TV 4K Dolby Atmos Sound Drops (Soundbar & Receiver)

The Quick Answer (TL;DR): Sound drops on Apple TV 4K are usually caused by bandwidth limitations in the HDMI chain. To fix it quickly: switch to a Certified Ultra High Speed (48Gbps) HDMI cable and ensure your TV’s audio output is set to "Passthrough" (not Auto/PCM).

Symptoms

• Audio cuts out for 1-2 seconds intermittently during playback.
• No sound or distorted popping when playing Dolby Atmos content (Netflix, Disney+).
• The "Dolby Atmos" badge flickers on your receiver/soundbar display.

Solution 1: The Cable Bandwidth Test (Most Common)

Apple TV 4K sends Dolby Atmos as "LPCM" (high bandwidth uncompressed audio), which is much heavier than the compressed audio from a Roku or Fire Stick. Your old "High Speed" cables might work for video but choke on the audio.

1. Check the Label: Look at your HDMI cable. If it does not explicitly say "Ultra High Speed" or "48Gbps", it is likely the bottleneck.
2. Swap the Chain: You need high-bandwidth cables for both connections:
   • Apple TV -> Soundbar/Receiver
   • Soundbar/Receiver -> TV (eARC port)

Solution 2: The "Passthrough" Fix

TVs often try to process the audio before sending it to the soundbar, causing sync issues and drops.

1. On your TV Settings (Samsung, LG, Sony, etc.):
   • Go to Sound > Advanced Settings.
   • Find Digital Sound Output or HDMI Audio.
   • Change it from "Auto" or "PCM" to "Passthrough".
2. On your Apple TV:
   • Go to Settings > Video and Audio > Audio Format.
   • Ensure Change Format is OFF. (If you turn it On, you lose Atmos).

Solution 3: The "Chroma" Tweak

Sometimes the video signal is taking up too much bandwidth, leaving no room for audio. Lowering the video chroma can stabilize the stream without noticeable visual loss.

1. Go to Settings > Video and Audio.
2. Change Chroma from 4:4:4 to 4:2:0.
3. Restart the Apple TV.

Is it still broken?

If you have replaced the cables and fixed the settings but the sound still drops, your soundbar or receiver might have a failing HDMI board (common in older units).

Pro Tip: Before buying a new soundbar, try plugging the Apple TV directly into th