The running sounds for vanilla horses are pretty great. Unfortunately, it appears that genetic horses don't use these particular sounds.
Any chance of this being changed in the future?

Version please, this used to work

At the time of posting, it would have been the latest version on Modrinth, 1.20.1-13.2.

I’ve double-checked and done some tests with only Realistic Horse Genetics installed.
For 1.20.1 (Forge: 47.3.0, 47.2.0, and NeoForge: 47.1.105), I tried 13.2, 12.6, 12.4, 11.5 via Modrinth and 13.0 via Curseforge.
I also tested:
1.19.2-13.1, 1.17.1-1.7.1, 1.15.2-1.4.0.1 via Modrinth
1.15.2-(1.5.1.2, 1.3.6, 1.2.4, 1.2.3) via Curseforge

Really wanted to be thorough. After 1.15.2-1.2.3 I tried 1.15.2-1.1.3 and can confirm 1.1.3 has running sounds for genetic horses. Unfortunately I don't think any version after that one has the running sounds for genetic horses.

I hope this information helps, your mod is brilliant! I hope it's an easy fix. I'd be very happy to assist if you'd like a hand testing any fixes.

Wow, that's been broken a lot longer than I realized. Thanks for doing such a thorough check. I'll see if I can get this fixed.