I've read on various posts that using sideloaded apps can cause "notifications" to be sent to the device (shield pro) which causes it to wake up in sleep mode.
I know one option is to turn off CEC control, but I'm attached to this feature, lol. SmartTube has become rather popular, does anyone know if it's possible to disable this? I did a skim through the options but didn't see anything related. I'm at the point where I'm going to uninstall it because the lights are waking me up at 3 a.m- but I'd rather not 😅
Press and hold on SmartTube app > info and check if notifications are turned off. If still happens then check with developer. He has a telegram group for issue reporting.