@Paulojr67
Can't really explain why your RokuTV is taking about a min to turn on. The only real way to speed that up is to change a settings that enabled a "fast start" mode. Rather than actually powering off, goes into more of a standby mode. (Settings/System/Power/Fast TV Start)
On my RokuTV, I normally find that performing a System Restart will temporarily help with the sluggishness. This should help to clear out the cache occasionally. (Settings/System/Power/System Restart). My Roku occassionally experiences this issue as is likely just a limitation of the memory hardware. My other regular TVs with an attached Roku device perform much better and faster so that is my general preference for a Roku setup. Others have no issues with their RokuTVs with performance so likely hardware differences between models.
Some have actually found that if their RokuTV is particularly old, then attaching a newer Roku device to the TV has improved their performance since all the Roku activity is now handled by the device rather than the integrated RokuTV.
There are a couple of different issues going on with the OTA channels (antenna tv) with the OS11 update. If you are experiencing the black screen when using Up and Down arrows while trying to change channels, then you will find that you have to enter the guide first before changing channels. When in OTA mode, press the Left Arrow to first bring up the Channel and Program Guide. Then navigate Up and Down from within the Guide to select your desired channel.
Roku is aware of the issue as there are a few other postings in the Community regarding this.
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If you continue to encounter issues, then you can always consider a Factory Reset which will hopefully clear out any corrupted data and return TV back to the day you bought it. (again, hopefully - not guaranteed). (Settings/System/Advanced System Settings/Factory Reset)
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
