How To Fix SuperBox Picture But No Audio In 2026

Your SuperBox S4 Pro shows a flawless picture, but there’s zero sound coming out of the box, the volume is turned all the way up, and nothing is muted, yet your TV happily plays audio from every other input.

Don’t worry, your box almost certainly isn’t broken. In nearly every case this is a single audio-output format setting sending a signal your TV or soundbar can’t decode, not failed hardware.

Below you’ll change one value in the Sound menu, and most people get their audio back in under 2 minutes without unplugging anything. If that doesn’t do it, we’ll walk the isolation tests that pinpoint a true hardware fault.

At a glance: the settings that cause silence in 2026

The picture travels fine over HDMI, but the audio is encoded in a format your TV can’t read. Picture but no sound is the classic signature of a bitstream/format mismatch.

Here are the three values to check first.

Setting	Wrong value (silent)	Correct value
Audio Output Mode	Bitstream / RAW / Dolby	Set to PCM or Auto
Digital Audio Output	Off / SPDIF (when on TV)	HDMI (or SPDIF for optical)
Dolby Digital	On (TV can’t decode)	Toggle off if TV can’t decode

Why does SuperBox show a picture but no sound?

Video and audio ride the same HDMI cable but are handled separately. Your TV decodes the video without issue, so you see a perfect picture.

The audio is a different story. If the box is sending a Dolby Digital or other compressed bitstream that the TV or soundbar can’t decode, the device simply outputs silence instead of static.

• Picture works, so the cable and port are fine.
• Silence on this input only points to format, not volume.
• PCM is a universal stream nearly every TV can decode.
• A Dolby/bitstream the TV can’t read equals picture but silence.

That’s why the same box can be silent on one TV and loud on another: it comes down to what each TV can decode, not the box itself.

How do I change the audio output to PCM?

This is the confirmed #1 fix. Forcing PCM makes the box send audio your TV is guaranteed to understand.

1. Press Settings on the SuperBox remote.
2. Open Settings > Sound (or Audio).
3. Set Audio Output Mode to PCM or Auto.
4. Set Digital Audio Output to HDMI.
5. If a Dolby Digital toggle is on and your TV can’t decode it, turn it off.

Sound usually returns instantly. If it does, you’re done: it was a format mismatch.

Using a soundbar or AV receiver with HDMI-ARC?

When a soundbar sits in the chain over HDMI-ARC, it has to decode whatever the box sends. A bitstream the soundbar can’t handle causes the same silent picture.

Setting the box to PCM forces a universally-decodable stream that the soundbar can play.

• Keep Audio Output Mode on PCM.
• Confirm the TV’s HDMI-ARC port is the one in use.
• Make sure the soundbar input is set to ARC or HDMI.

Reboot the box and reseat the cable

A quick power cycle clears a stuck audio handshake (HDCP/EDID) between the box and TV. Do this before assuming anything is wrong.

1. Unplug the SuperBox from power for 30 seconds, then plug it back in.
2. Unplug the HDMI cable at both ends and firmly reseat it.
3. Power the box back on and recheck audio.

A loose or half-seated HDMI connector can pass video while dropping the audio handshake.

Try a different HDMI port and cable

Not every HDMI port behaves identically. Some TV ports handle audio return or specific formats differently, and a marginal cable can carry video but corrupt audio.

• Move the box to a different HDMI port on the TV.
• On many TVs, prefer the port labeled HDMI 1 or the ARC port.
• Swap in a known-good high-speed HDMI cable.

If a new port or cable restores sound, the original was the culprit.

Bypass the receiver or soundbar to test

Extra devices in the chain add places for the audio to break. Testing the box plugged straight into the TV isolates the problem fast.

1. Disconnect the box from the AV receiver or soundbar.
2. Plug the SuperBox directly into the TV’s HDMI port.
3. Set the box to PCM and check for sound.

If audio works directly into the TV, the receiver or soundbar (or its settings) was blocking it. From there you can reintroduce the soundbar with the box on PCM and confirm it stays working.

What if there’s still no sound?

If you’ve set PCM/Auto and tested every port, cable, and TV with no audio at all, you may have a genuine hardware fault. Use this checklist to confirm.

Test	What it tells you
Different HDMI port, PCM set	Sound = bad port. Silence = look further.
Different HDMI cable	Sound = bad cable. Silence = look further.
Box straight into a second TV	Sound = first TV/chain issue. Silence = box hardware.
Direct to TV, no soundbar	Sound = soundbar/receiver issue.

No audio across every port, cable, and TV even on PCM points to a hardware fault, so check warranty or replacement.

If changing the setting didn’t work: an HDMI audio extractor

For stubborn format or HDMI-ARC mismatches, an HDMI audio extractor pulls audio out as optical (SPDIF) or 3.5mm, sidestepping the format your TV can’t decode. One verified option is the WARRKY 4K HDMI Audio Extractor.

Spot-check before buying: confirm it offers a PCM/stereo (2.0CH) output mode, since that’s the stream your TV or speakers are most likely to play.

A note on honesty and the gray area

Some older SuperBox models are discontinued, and SuperBox IPTV itself sits in a legal gray area. None of that changes this specific problem.

Picture but no audio is a local audio-output configuration issue on the box, and it’s almost always fixable by you in a couple of minutes.

Quick reference

Step	Action
1	Settings > Sound, Audio Output Mode = PCM/Auto
2	Digital Audio Output = HDMI (or SPDIF for optical)
3	Turn off Dolby Digital if TV can’t decode it
4	Reboot box, reseat HDMI, try another port/cable
5	Plug box straight into TV to bypass soundbar/receiver
6	Still silent everywhere on PCM = hardware fault (warranty)