Do Fuses make a difference ib sound?

Definitely yes. They are also directional. Just turn yours 180 degrees and see whether you can tell the difference. If you can try the Digital Fuse Box,

Potentially burning the house down as another poster seems to recommend seems to me a matter of personal preference, though

I swapped out a bunch of fuses in amp, preamp, streamer, DAC and DDC in main rig which is pretty resolving.  I couldn’t tell much of a difference, if any.

It will be hard to test in a way that keeps you "blind" to the outcome. So, it will come down to your own ability to distance your perception from your preconceptions and desires. Good luck!

I take it that the fuses in question are 5x20 internal or 6x32. Not UK 6x25 plug fuse.

Fuses adapt over time to a device and work more OK when the difference between them and the board they are in is complimentary.

This means that a good deal of fuse are a waste of time. Also many fuse are not slow blow, so one should be considerate there.

To change and get an improvement I would recommend Aucharm (not slow blow) or Isoclean (either), I am fully impressed with Isoclean 10A and Aucharm other values. I ran tests on phonosophie and Synergistic Red over 10 years (just keeping an eye on them), and they failed my test of worth significantly.

I build power Cables for people in the UK, so we have them built into our Mains Plugs. Which is an absolute enemy.

Main power fuses inside the component can influence sound quality, and just like power cables - it depends. HiFI tuning fuses from Germany for around $100 is a safe bet (they are directional too). After running them for a week or two put the old fuse back in to gauge difference. I noticed positive change in Eversolo DMP A10 streamer/DAC, some improvement in PL integrated tube amp.