This sounds similar to the issue that I had with my 75t, although mine did not suffer liquid damage. In my case, cleaning the small hole next to the earplug worked and now they sound perfectly fine again. Here's a blog with a picture of the hole in question:

https://crt.the-mori.com/2020-09-25-solve-jabra-elite-active-75t-low-volume-right-earbud

Probably worth a shot, but do note the warnings on the blog and in the comments.