Samsung smart TV intermittently ‘glitching’

[Guineafowl]

TL;DR

Our nine year-old TV has started to develop odd, intermittent, glitchy behaviour. Would it be wise to leave it until a hard fault develops, or do some preventive maintenance?

Model UE55NU8000T, with a ‘smart’ remote operating on Bluetooth (except for the power button, which is IR) and a normal one, which is all IR.

Intermittent faults:
- Loses BT pairing with the smart remote. Sometimes will not re-pair unless the TV is unplugged/plugged at the wall. Always works with the IR remote, except for one case, see below.
- Loses pairing (again BT) with the soundbar.
- Switches on, then off a few seconds later.
- Sometimes will fail to power off (to standby) for about 10 seconds, with either remote.

Steps taken, to no avail:
- Smart remote batteries changed.
- Latest software update.
- Unplugged from wall and power button held for 30 seconds.
- Factory reset.

Given the TV has been powered for nine years, I’m starting to wonder about the power supply electrolytics. Would others dive in and recap the board, or leave it till something more obvious develops, or something else?

I should note, I’ve recapped various appliances over the years - scopes, sound equipment, vintage radios - so am quite happy with the technique and safety aspects.

 

[Greg Bernhardt]

Something wrong with the power supply. Can you do a safe visual check for anything that looks suspect?

 

[Guineafowl]

I can’t see much from the outside. No access panel for the power board so it’ll be a case of spudging horrible plastic clips all the way around to get inside.

 

[robphy]

Could it be WiFi interference?

Although not specifically about televisions,

Make sure your router is set to only use 20MHz-wide channels. Wi-Fi can do 40MHz-wide channels in 2.4GHz, but it doesn't leave enough room for other users of the band, such as Bluetooth.

seems to have helped some folks in that thread.

 

[Guineafowl]

Could it be WiFi interference?

Although not specifically about televisions,

seems to have helped some folks in that thread.

I was having trouble logging in to the router gateway, but am in now.

It uses 2.4 and 5 GHz channels. The 2.4 channel width is already set to 20 MHz. The 5 is set to auto (20/40/80 MHz), but has an option to force 20 MHz only.

The bluetooth remote apparently uses the 2.4 GHz band, so would there be any benefit to setting the 5 to 20 MHz width?

 

[robphy]

I was having trouble logging in to the router gateway, but am in now.

It uses 2.4 and 5 GHz channels. The 2.4 channel width is already set to 20 MHz. The 5 is set to auto (20/40/80 MHz), but has an option to force 20 MHz only.

The bluetooth remote apparently uses the 2.4 GHz band, so would there be any benefit to setting the 5 to 20 MHz width?

From what I understand of the reddit post I linked, since Bluetooth uses 2.4GHz, it would be good to get the 2.4GHz-wifi width as small as possible (which you report already is set there at 20MHz). But I don't think changing the 5GHz settings has any effect on your bluetooth problem.

Can your smart tv use the 5GHz wifi?
Is your router near your tv?

 

[Guineafowl]

The smart TV can use the 5 GHz, but doesn’t as it has a direct ethernet cable connection. Router is about 6m from the tv, but with no line of sight.

I’ve restricted the 5 GHz channel width to 20 MHz anyway, but such is the joy of intermittent faults, I’ll have to wait a week or so to see if it’s done any good.