I just ripped 10,000 tracks to ALAC and installed a Tonbux MXQ with a palm-sized keyboard for easiest searching. Now, I'm trying to learn a commands (NOT the alphanumerics) into my Pronto NG 7500. It's impossible to learn a single button! Meanwhile, neither Tonbux nor MXQ can be found searching Remote Central.

Question: do some remotes use a type of infrared that is not compatible with Pronto?

There is a "MXQ Media Manager 4k Android TV" on irdb.globalcache.com . These are just normal NEC1 commands with deviceno 1.

POWER TOGGLE:

0000 006C 0022 0002 015B 00AD 0016 0041 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0041 0016 0016 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0016 0016 0041 0016 05F7 015B 0057 0016 0E6C

900A 006C 0000 0001 01FE 40BF

Possibly this helps you.

Those codes are for the small remote, and don't work for the MXQ's palm-sized alphanumeric keyboard.

Could be possible but the only IR codes we've ever had issues learning are rolling codes. First push sends code A, second push code B then back to A etc.

There are protocol with an ending sequence, like NRC17. This cannot be represented by pronto hex. But in general the receiving devices are forgiving in the case of omitted ending sequences, so they work satisfying anyhow.

Can it be that your thing does not use IR at all? Instead RF/Bluetooth/WiFi?

How can I tell?

For example,

1. Digital cameras, like a smartphone, can "see" it,
2. IR receivers like a learning remote (e.g. your Pronto) can detect it,
3. Ir signals can are blocked by non-transparent objects, like a hand. Radio signals go through.