Direct answer
For the Roku Streaming Stick 4K, output selection, mute/volume, format and the external audio path should be isolated. First, test TV speakers with a built-in app and PCM/stereo output.
What this covers
- Roku Streaming Stick 4K (3820X/3821X)
- Roku player or Roku TV family; remote type, Wi-Fi radio, Ethernet and Dolby formats vary by model.
- The specific fault this record addresses: has picture but no sound
What it does not cover
- ×The same symptom on a different Roku product line, which has its own record and its own cited source
- ×An on-screen error code whose meaning has not been checked against this exact model's manual
- ×Live electrical, gas, sealed-system, internal battery-cell or structural repair — a technician boundary, not a self-service step
Differential
What actually causes this, and how to tell them apart
These are ordered by how often each one is the answer, not by how easy it is to try. The point of the middle column is that two causes producing the same headline symptom rarely produce the same detail — that detail is what tells you which one you have before you change anything.
- 1
Audio output is routed to a device that is off or disconnected
What separates it No sound from the TV speakers, with an external audio device selected in the sound settings.
How to confirm Set the output explicitly to the internal speakers as a test. If sound returns, the fault is in the external path rather than the set.
- 2
The audio format is one the connected device cannot decode
What separates it Silence on specific apps or sources — typically Dolby Atmos or DTS content — while others play normally.
How to confirm Set the output format to PCM or Stereo as a test. If sound returns, the format was the problem and the receiving device does not support what was being sent.
- 3
Bluetooth headphones are still connected
What separates it No sound from the speakers or the soundbar, with a pair of headphones powered on somewhere in the room.
How to confirm A television that auto-reconnects to previously paired headphones mutes its own output silently. Disconnect them in the Bluetooth settings.
- 4
The set is muted or volume is at zero on a second control
What separates it No sound with the volume apparently up, in a setup with more than one remote.
How to confirm Where a soundbar or receiver handles audio, the TV's own volume may be irrelevant and the other device muted.
- 5
The streaming player's audio settings do not match the display chain
What separates it Silence from one streaming device while the TV's other inputs play normally.
How to confirm A streaming player has its own independent audio output settings. Setting it to stereo or PCM confirms whether a surround format is the cause.
- 6
The internal speakers or amplifier have failed
What separates it No sound from the internal speakers on any source and any format, while headphones or an external output work.
How to confirm This is the conclusion once routing, format and mute state are eliminated, and is a service repair.
Before you touch a setting
Record this first — changing settings destroys the evidence
Every item below stops existing the moment a reset, re-pair or settings change is made. Written down first, they are what separates the causes above; recovered afterwards, they are guesswork.
- Whether the internal speakers are explicitly selected as the audio output.
- Whether silence affects every source and app, or only specific ones — the latter points at audio format.
- Whether any Bluetooth headphones are paired and powered on nearby.
- Whether a soundbar or receiver is in the chain with its own separate volume and mute.
Set the audio output explicitly to the internal TV speakers
ReversibleThis separates a set with no sound from a set sending sound somewhere you are not listening.
Set the audio format to PCM or Stereo as a test
ReversibleIf sound returns, a surround format was being sent that the receiving device cannot decode.
Check for connected Bluetooth headphones and disconnect them
ReversibleA set that silently auto-reconnects to previously paired headphones mutes its own output with no indication.
Check mute and volume on every remote in the chain
ReversibleWith a soundbar or receiver present, the TV's own volume may not be the one that matters.
Confirm sound on a built-in app before blaming an external device
ReversibleA built-in app bypasses the whole HDMI chain and isolates the set itself.
Model-specific
What is true of this model and not of its siblings
Generic advice for the product line fails here. Each item below is a property of this specific model family that changes which of the steps above apply to you.
- Model scope
- 3820X/3821X. Roku player or Roku TV family; remote type, Wi-Fi radio, Ethernet and Dolby formats vary by model.
- Device type — streaming player, not a TV
- A stick that plugs into an HDMI port; no panel of its own, so picture adjustments are made on the TV. Runs Roku OS.
- HDR — Dolby Vision, unlike the Express 4K
- The Streaming Stick 4K adds Dolby Vision on top of HDR10 and HDR10+ — the cheaper Express 4K does NOT have Dolby Vision. If you moved from a Stick 4K to an Express 4K and lost Dolby Vision, that is the model difference, not a fault.
- Connectivity — long-range Wi-Fi, no Ethernet
- Has an improved long-range dual-band Wi-Fi receiver but NO Ethernet port (only the Ultra has that). It is powered from the TV's USB port or the supplied adapter — a stick that reboots or drops out is often being underpowered by a weak TV USB port, so use the wall adapter.
- Symptom boundary
- This record covers Roku Streaming Stick 4K when it has picture but no sound. A different symptom on the same hardware, or this symptom on a different Roku product line, has its own record with its own causes and its own cited source.
Stop boundary
When this stops being a self-service repair
Continuing past any one of these costs more than the repair saves — in safety, in warranty, or in evidence a technician needs.
- !Unplug for a burning smell, distortion accompanied by heat, or visible damage at the rear panel.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Where the manufacturer's article stops. Roku publishes this as "What to do if you do not hear sound from your Roku® streaming player". Roku's no-audio article for a streaming player that has picture. Probed 2026-08-21: title-verified. What that article does not carry is the model boundary — it is written for a product line, and 3820X/3821X is the scope applied here. Where a control label, terminal, indicator pattern or reset sequence differs on your unit, the manual for that exact model is the authority, not this page and not the article.
Exact questions
Common follow-ups
My Roku Streaming Stick 4K keeps restarting or won't power on.+
The most common cause is power. The stick draws more than some TV USB ports supply, so if it is powered from the TV's USB it can brown-out and reboot — plug it into the included wall adapter instead. Also make sure it is on an HDMI port with the extender cable if the signal is weak. It has no Ethernet, so persistent drop-outs after that are Wi-Fi range.
Sound works on some apps but not others.+
That pattern almost always means an audio format problem rather than a hardware one. The silent apps are likely sending Dolby Atmos or DTS that something in your chain cannot decode. Set the TV's audio output format to PCM or Stereo as a test — if sound returns, that confirms it.
The TV suddenly has no sound at all.+
Check whether a pair of Bluetooth headphones is powered on somewhere in the room. Televisions silently auto-reconnect to headphones they have paired with before, and when that happens the set mutes its own speakers with no on-screen indication at all.
Does this answer apply to every Roku model?+
No. It is scoped to 3820X/3821X. Roku player or Roku TV family; remote type, Wi-Fi radio, Ethernet and Dolby formats vary by model.
What should I record before troubleshooting no sound or audio?+
Record the complete model identifier, exact message or indicator, software/firmware where visible, the operating stage and what still works.
Why is a factory reset not the first step?+
A reset can erase accounts, networks, maps, schedules or preferences without distinguishing no sound, audio. The ordered checks preserve that evidence.
When should I stop and use qualified service?+
Stop for electrical noise, heat, sparks or repeated receiver protection.
Answer for the exact device and software version shown above.