Choose output behavior deliberately
Roku’s auto-adjust display refresh rate lets compatible players switch output timing for supported content. Roku notes that some apps do not use the feature. Turning it on is therefore not a guarantee that every programme or application changes mode.
Identify the actual player before searching for the option. A Roku TV, an older player and a current compatible player should not be treated as identical products simply because they share a brand.
Enable the documented option
Roku’s guide places the control under Settings, System, Advanced system settings, Advanced display settings, Auto-adjust display refresh rate. Use it where present and record its original state.
Compare a familiar programme with visible motion and keep the TV’s motion processing fixed. If the television shows received timing, note that independently of how smooth the picture appears. Source cadence and TV interpolation are separate factors.
Expect a possible format transition
Roku explains that changing display modes can cause a brief black flash when playback starts or stops. This may occur more often in apps that preview video while browsing. Decide whether the cadence benefit and transition behavior suit the household.
A short transition followed by stable playback is different from a picture that never returns. If the latter occurs, investigate the supported display route rather than accepting every blank screen as normal switching.
Respect the application boundary
Roku identifies app exceptions, including Netflix and Hulu in its current guide. If a selected app stays at the regular output rate, check that support scope before replacing cables or changing accounts.
Record the player, app, option and observed timing when seeking help. This page explains the official control and does not claim a measured comparison of film motion or universal player compatibility.
Questions answered
Will every app change frame rate?
No. Roku documents exceptions for some apps.
Can a short black flash be expected?
Roku says a television mode change can cause it at playback transitions.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.