Thanks for the clarification. I didn't recognize MHZ as a channel, so I looked in the channelstore. So I'm assuming you are referring to MHz Choice. According to the listing, it's provided by MHz Networks, and the same basic response about the ability to adjust speed applies here as well. MHz Networks provides the app for Roku devices, and they are the only ones that can answer any questions about their app functionality. It's possible the ability to control playback speed simply isn't possible on the Roku OS, although from the sounds of it other channels have offered it in the past. If it's available, then it's up to the app developer to make it work on their app. Roku doesn't have control over how the player works within a specific app from a 3rd party. You can contact MHz Networks here: https://support.mhznetworks.com/support/home
Dan
Roku Community Streaming Expert
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