Fix SuperBox HDMI No Signal After Standby (2026)

Your TV flashes “No Signal” on the SuperBox input even though the box’s lights are glowing and it clearly has power, and it almost always happens right after the box wakes from standby.

The good news: this is rarely a dead box. It’s nearly always a stuck HDCP handshake, a resolution mismatch, or an ARC port that dropped the connection when the box and TV woke at different times.

Expect a fast fix. In 2026, swapping to a different HDMI port plus a clean power-cycle of both devices clears the large majority of these cases in just a few minutes, and the rest come down to cable or resolution settings.

Start Here: The At-A-Glance Fix List

If you only do one thing, move the cable to a different HDMI port first. A real S6 Max user reported that simply switching to and resetting HDMI 2 restored the picture. Then power-cycle both devices to force a clean handshake.

Fix	What it addresses	Time
Switch HDMI port (non-ARC)	Failed handshake on wake	1 min
Power-cycle TV + box	Stuck HDCP handshake	~2 min
Lower resolution to 1080p/60	Resolution/refresh mismatch	2 min
New short HDMI cable	Bad or marginal cable	2 min

Work top to bottom and stop as soon as the picture returns.

Why Does SuperBox Lose Signal After Standby?

When the SuperBox sleeps, the HDMI link goes idle. On wake, the box and TV must renegotiate the HDCP copy-protection handshake and agree on a resolution and refresh rate.

If the TV wakes a moment later than the box, that handshake can fail. The result is “No Signal,” sometimes with a brief flicker as the box tries and gives up.

The box is powered, so its lights stay on.
The TV never receives a valid signal, so it reports nothing.
A full power-cycle resets both ends and forces a clean handshake.

This is a timing and handshake problem, not a broken box.

Fix 1: Switch To A Different HDMI Port

This is the confirmed working fix and your first move. Different ports on a TV often behave differently after standby.

Unplug the SuperBox HDMI cable from its current port.
Plug it into a different port, ideally HDMI 2.
Switch the TV’s input source to match the new port.

If the picture returns, the original port was mishandling the wake-up handshake. Leave the box on the working port and you may never see the issue again.

Fix 2: Power-Cycle Both The TV And The Box

A stuck HDCP handshake clears only when both devices fully reset. A quick remote-off is not enough; you need to pull power.

Turn off the TV and unplug it from the wall.
Unplug the SuperBox power adapter.
Wait about 1 minute so both fully discharge.
Plug the TV back in first, then the SuperBox.

Powering the TV first means it is fully awake and ready to negotiate when the box boots, which is exactly the condition that fails after standby.

Does The HDMI Port Matter (ARC Vs Non-ARC)?

Yes, and it matters a lot. The ARC (Audio Return Channel) port renegotiates audio routing on wake, and that extra step often drops the video handshake with it.

Most TVs label the ARC port directly, for example “HDMI 2 (ARC)” or “eARC.”

Avoid the ARC/eARC port for the SuperBox.
Use a plain HDMI input with no audio-return labeling.
Let your soundbar or AVR keep the ARC port for itself.

Moving the box off the ARC port removes one handshake hop that frequently fails after standby.

Fix 3: Lower The Output Resolution To Match Your TV

If the box outputs 4K or “Auto” but the TV negotiates a lower mode on wake, the mismatch shows as “No Signal.” Forcing a safe, fixed mode removes the guesswork.

On the SuperBox, open Settings > Display and set the output manually.

Set resolution to 1080p instead of 4K/Auto.
Set the refresh rate to 60 Hz.
Save and reboot the box once.

1080p/60 is the most universally supported mode, so almost every TV accepts it instantly on wake. You can step back up to 4K later if your TV proves stable.

The Soundbar / AVR Trap

Routing the SuperBox through a soundbar or AV receiver adds another handshake hop. Every device in the chain must complete its handshake on wake, and any single failure breaks the picture.

To isolate this, bypass the audio gear temporarily.

Unplug the SuperBox from the soundbar or AVR.
Plug it directly into a non-ARC TV port.
Test waking from standby a few times.

If a direct connection is stable, the soundbar is the weak link. Update its firmware or keep the box plugged into the TV and use ARC for sound.

Fix 4: Reseat Or Replace The HDMI Cable

A marginal cable can pass a picture cold but fail the higher-bandwidth renegotiation after standby. Reseating sometimes helps briefly, which is itself a clue the cable is borderline.

Use a short, certified high-speed HDMI 2.0 cable. Shorter runs hold the signal better and renegotiate more reliably.

The Highwings 0.5ft 4K High-Speed HDMI Cable is an inexpensive, well-rated short option rated for 18 Gbps, 4K@60Hz, and HDCP 2.2. Spot-check the listing for current price and length before buying, since sellers rotate variants. If you can’t verify the listing, any certified high-speed HDMI 2.0 cable under 3 feet does the same job.

Disable Deep Color And HDMI-CEC If They Interfere

Some TVs run extra HDMI features that complicate the handshake. Two are worth toggling off when nothing else works.

HDMI Deep Color (sometimes “Enhanced” or “UHD Color”) can demand bandwidth the link can’t sustain on wake.
HDMI-CEC (named Anynet+, Bravia Sync, SimpLink, and others) can power devices in the wrong order.

Find these in the TV’s HDMI or external-input settings, turn them off for the SuperBox port, then reboot and retest. Re-enable them one at a time if you want CEC’s one-remote convenience back.

What If Every Port Still Says No Signal?

If you have tried every port, a known-good short cable, a direct-to-TV connection, and a forced 1080p/60 output and the box still shows nothing, isolate the box itself.

Test	Result: works	Result: still fails
Different TV port	Original port faulty	Not the port
Different cable	Cable was bad	Not the cable
Different TV entirely	First TV’s HDMI/settings	Box HDMI output suspect

If it fails on every TV, port, and cable, the box’s HDMI output may be faulty. Contact SuperBox support about warranty or replacement.

A Note On Older Boxes And Honesty

Some older models, including the S3 Pro, are discontinued and show a black-screen variant of this same issue. The troubleshooting above still applies, but support and firmware updates may be limited.

To be clear on two points:

This is a hardware and handshake issue. SuperBox IPTV streaming sits in a legal gray area, but a “No Signal” screen is purely about HDMI, not content.
If a known-good setup fails everywhere, accept that the HDMI port hardware may simply be dead and plan a replacement.

No setting will revive failed output hardware.

Quick Reference

Situation	Most likely cause	Do this
No Signal only after standby	HDCP handshake on wake	Power-cycle both, ~1 min
Flicker then No Signal	Resolution/refresh mismatch	Set 1080p/60 in `Settings > Display`
Drops when soundbar is on	ARC handshake hop	Plug box direct to non-ARC port
Reseating helps briefly	Marginal cable	Use short certified HDMI 2.0 cable
Fails on every TV/port/cable	Faulty HDMI output	Warranty / replace box

How To Fix SuperBox HDMI No Signal After Standby In 2026