I'm running Emacs 25.1.1 on Debian. No particularly elaborate setup.
I recently bought a new mouse, a Logitech MX Anywhere 2S, though I am not using any of the "programmable" features. I simply use the mouse via Bluetooth. I haven't changed anything anywhere.
It works fine in every other application, but in Emacs, when I try to scroll, I get beeps and
C-M-( [or C-M-)] is undefined.
mouse-wheel-mode is enabled.
The other aspects of the mouse work as expected; I can paste using the middle button, for example.
Any thoughts on how to fix this?