UDP does not itself provide TCP-style ordered reliable delivery. Applications using it must handle their own needs for timing, recovery or concealment. That can make loss appear differently, but the actual result depends on the media protocol and player.
Do not infer transport from a symptom
A blocky frame does not prove UDP, and a loading spinner does not prove TCP. The player or service documentation is a better source for the transport in use. Packaging names and transport names also describe different layers.
Prioritise a sound local link
A stable wired or well-performing wireless connection helps regardless of transport. Compare the same authorised source while leaving player settings unchanged. Avoid opening arbitrary router ports based on assumptions about UDP.
Respect service configuration
Switch protocols only through a supported application option and according to provider guidance. A server must actually offer the alternative. Replacing text in a URL does not create another transport endpoint.