I need my Tab-E to run video for weeks at a time

[Macadoo]

Hi everyone
I've been working on this sculpture for some years now and have run into a problem. Because of the nature of the sculpture, and the typical length of an art exhibition, I need the Tab-E (SM-T560NU) to run video constantly for weeks at time (typical show is 3-4 weeks), but it only runs for a few days before going to sleep.
I've enabled developer settings, and turned on the stay awake feature, turned off all the apps I'm allowed, and keep the unit in airplane mode. I've also replaced the battery with a battery "blank", using the voltage regulator from the old battery, so there is no chemical warming. The Tab-E runs fairly cool, compared to another Tab-E I have that's not mounted on the sculpture. The unit loops about 60 videos, and I tested it before fitting it to the sculpture, and let it run for a couple of weeks.
I'm using MX Player Pro for the player, as I like the zoom features for the faces (see below video). I suppose it could be a software issue, rather than hardware, but my gut says no. But, if there's a better player, I'm open to the idea. Here's the sculpture, iRobot: If you prick us, do we not bleed?
Many thanks, and all ideas welcome.
-Mac

 

[Macadoo]

I should have mentioned, the video has an old Nook tablet that wasn't capable of more than a couple videos. I've since refitted the sculpture with the Tab-E.

 

[Macadoo]

I'm not sure what you mean, Zaqon. Spreading it?

So, I missed another important detail. When I brought the Tab-E out of sleep mode, the video plyer had turned off. So maybe it is the player.
Thoughts?

 

[svim]

https://www.gsmarena.com/samsung_galaxy_tab_e_9_6-7295.php

I'm just guessing that it's not an app issue (in this instance MX Player Pro) nor a hardware issue (dated but still capable model), but rather just a quirk with the installed Android operating system. Taking into consideration all the things you've done to the base power management and most importantly that you're able to get several days of continuous usage, this might be just a matter where there is an overriding, integral sleep mode with the OS that kicks in after a several days, despite the lower level config changes you've made. Have you tried using Screen Pinning? (e.i. pin the screen with just the MX Player Pro app selected)
https://support.google.com/android/answer/9455138?hl=en
Or have you looked into any third-party app solutions that prevent sleep mode or enable kiosk mode? (When researching online, be sure to take into account the vintage of the OS this tablet is running, and note that most kiosk apps are pay-for if budget is a factor).

 

[Macadoo]

Thanks for the tips, svim, and the links
I've got the app pinned now (didn't know this was possible, so thanks), and running, so we'll see how long it runs. I don't mind paying for a good third-party app, but I won't rent.
Now that I'm thinking of it, I should probably go through all the phones in the spine and pin the app there, just for good measure. But I'll see how this works out, first.
Again, much appreciated