JP1 Remotes

[Wiley1]

I need a remote that will do just these three things:

Control a Tivo Mini
Control power and volume on a Fosi amplifier
Control power and a few other buttons on a Samsung TV

Seems simple, right? Except that I also need it to be fully waterproof.
I thought I had struck gold when I found this learning remote that floats in my hottub:
https://www.ebay.com/itm/224433405063

It works nicely with built-in codes for the Samsung and learned codes for the Fosi. But, I have been unable to get it to learn any Tivo code.
So, I need to find a way to make this remote do the job, or find another remote that meets my requirements.

Is there something non-standard about Tivo codes that makes them incompatible with my learning remote?

Is there a waterproof remote out there someplace that can learn Samsung, Tivo, and Fosi?

I've tried everything I know to get the WP-1545AL1 to accept Tivo codes but nothing has worked. Does anybody have any suggestions?
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