@Rocki
While the Express 4K+ supports both 2.4 GHz and 5 GHz bands, do you know which it's using to connect? If it's using 2.4 GHz, and the channel is crowded (nearby, separate networks can affect it), it could interfere.
Confirm the band, and channel if possible, that Roku is using. Those other devices could be using the other band.
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
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