
We know this guy, the owner of the mice business. He's a great guy, and his mice are great mice, but he is a damn maniac, and always tries to squeeze crazy solutions into his mice' firmware. (but once again, his mice are great).
There is no way but trying and erring; disable first the mouse, then the kb, then both, and you will see which one was the culprit.
Don't forget to reboot every time you disable a device.
ATTENTION: you don't have to disable the physical device.
I mean, disable its advanced features, turn it into a simple Windows pointing device by temporarily disabling its proprietary software.Then reboot, set up your joystick, and see how it goes.