Fuse of Naim Uniti Star

Hi every one,
I would like to upgrade fuse of Uniti Star but i saw in box has two fuse as following the attached image. I have two concern for that.
The fuse second a back up is ?
The fuse of Star is 3.1A so can i change a fuse 2.5A ? Or must have = / > 3.1A

Thank so much for your help and share. Please !

Vu Nguyen

The second fuse is a spare, yes. You must always replace any internal fuse with the exact same type and rating - this is a critical safety point! DO NOT, whatever you do, try to “uprate” the internal fuse. Quite apart from invalidating any warranty, you will also potentially endanger yourself as well as anybody else living in your building should there be any critical failure of something like the transformer.