Ask which edition, not just which title
A show can have several viewing editions with different picture formats. Noxx identifies the production and opens its viewing choices. The service you select supplies the video, including the resolutions supported by that offer. A poster image does not establish that a 4K episode is available.
Use the screen as your guide
A small phone and a large television make different demands. Start with a setting your connection holds reliably. Automatic quality may adapt when conditions change. If a high setting repeatedly interrupts dialogue, a steady lower setting can be more enjoyable. HDR and surround audio are separate capabilities, not automatic consequences of a 4K label.
Older television
An earlier series may have a different aspect ratio, source format or restoration history. Do not stretch the image merely to fill the screen. Inspect the available edition, choose the intended framing and let the show look like itself. For repeated interruptions, use the playback help steps to distinguish a connection problem from a title-specific one.