First, confirm it is actually worse
Before hunting a fault, make the comparison fair. Test the same channel, at the same time of day, for the same length of time on each connection. Live streams vary enough minute to minute that a short comparison can mislead.
Also confirm the device is genuinely using the cable. Many devices keep an active Wi-Fi connection alongside Ethernet and may prefer it. Turning Wi-Fi off on that device removes the ambiguity entirely, and is worth doing before anything else.
The 100 Mbps port
The most common real cause. Not every Ethernet port is gigabit — plenty of streaming boxes, and a good many older routers and switches, have 100 Mbps ports.
That is still far more than a television stream needs, so it is rarely the direct cause of stutter. It matters when the same port carries other traffic at once, or when a device negotiates down to 10 Mbps because of a cable fault, which is genuinely too slow.
Most devices show the negotiated speed in their network settings. If it reads 10 Mbps, you have found your problem, and it is almost always the cable.
Cable faults that do not look like faults
Ethernet fails gracefully, which is unhelpful — a damaged cable often works while performing badly rather than not working at all.
- A crushed or sharply bent cable, particularly one run under a door or behind furniture, can lose pairs and drop to a lower speed.
- A loose clip means the connector sits imperfectly. If it does not click, replace it.
- Very old cable from a drawer may be Cat 5 rather than Cat 5e, which limits it to 100 Mbps.
- Long runs beside mains wiring can pick up interference, though this needs an unusually long run to matter.
Swapping in a known-good cable is a two-minute test that resolves most of this.
Powerline in the path
If your "wired" connection includes powerline adapters, it is not really a wired connection — it is a wired connection over your mains wiring, and it inherits every characteristic of that wiring.
Powerline can be excellent or poor depending on the circuit. It degrades when the two adapters are on different ring circuits, when a plug is on an extension lead rather than a wall socket, and when a heavy appliance switches on. If your streaming is worse in the evening specifically, and powerline is in the path, that is a strong hint.
Test by moving the device temporarily to a direct cable from the router, even if that means sitting in the wrong room for ten minutes.
Switches, and where they are
An unmanaged switch is usually invisible and fine. Two situations are not.
A very old switch may be 100 Mbps or, occasionally, a hub rather than a switch — which shares bandwidth across everything connected. And a chain of switches, each adding a small delay, compounds latency in a way that live television notices more than downloads do.
If there is a switch between your television and the router, try bypassing it as a test.
When Wi-Fi genuinely is the better choice
Occasionally it is, and it is worth saying plainly.
If the only wired route involves a long powerline run through a difficult circuit, and the television sits one wall from the router on a clear 5 GHz signal, Wi-Fi may well be steadier. The point of a cable is predictability, and a compromised cable path may have less of it than good Wi-Fi.
The general advice in Ethernet vs Wi-Fi still holds — a genuine direct cable beats wireless for live television. But "wired" covers a range of things, and some of them are not what that recommendation meant.
Frequently asked questions
Why is my IPTV worse on Ethernet than Wi-Fi?
Usually a specific fault in the wired path: a damaged or old cable, a port negotiating at 10 Mbps, powerline adapters on a poor circuit, or an ageing switch. Check the negotiated link speed in network settings first.
Is a 100 Mbps Ethernet port fast enough for IPTV?
Comfortably, for one or several streams. It only becomes a problem if the same port carries heavy traffic at once, or if a faulty cable causes the link to drop to 10 Mbps.
Do powerline adapters count as a wired connection?
Only partly. The data travels over your mains wiring and inherits its characteristics, so results vary between homes and can worsen when appliances switch on.
Should I turn Wi-Fi off after plugging in a cable?
It is worth doing. Some devices keep both active and may prefer Wi-Fi, so disabling it removes any doubt about which connection is actually carrying the stream.