We have two Rokus in the house. Roku #1:
Model: 3820X - Streaming Stick 4K
Version 11.5.0 build 4312-CU
I've known about the issue since December. It could've existed prior but I wouldn't know.
Tracker ID: SC-062-125
When the Speech Recognition box is unchecked under the Voice option in the Privacy settings, a popup window comes up saying "Cannot update setting. This setting couldn't be changed at this time. Please check your network connection and try again later." Once the window is closed and you leave and re-enter the Voice options, the check in the box appears again.
3910RW - Roku Express+
Version 11.5.0 Build 4312-51
Tracker ID: 63-062-135
FYI the Express+ will be replaced with another 3820X Streaming Stick once this privacy issue is fixed.