The keys 9 and 0 are, by default, volume- and volume+, respectively.
I often use this stats screen to check filenames and such:

Unfortunately, if I try to increase the volume too quickly after checking the filename, 0 instead changes the stats page to an unhelpful "Internal performance info" screen that looks like this until quitting mpv:

How can I remove this behaviour from the 0 key and make it always act as volume+ instead?
By re- or unbinding all offending (also script-specific) key binds.
While the stats script is active, its key bindings override any existing ones, but those can be changed or removed.
You can add the option
key_page_0=keytoscript-opts/stats.confin an mpv configuration location such as the following file:Unlike most configuration, this file is NOT cumulative with itself across locations. (everything from
/etc/mpv/script-opts/stats.confis ignored instead of added to if you also have~/.config/mpv/script-opts/stats.conf)Or append
stats-key_page_0=keyto thescript-optslist,such as, to unbind:
mpv --script-opts-append=stats-key_page_0=or in an
mpv.conffile:In the meantime:
You can revert the page back to "Show usual stats" by pressing
1while shown instead of restartingmpv. From the mpv manual: