I think diesel pusher gave you a bit of a hint, when it comes to looking for better fuses. The "audio engineer" hint reminded me that high power automotive stereo fuses have gold plated blades. You might want to hit up a local auto stereo shop, (that sells high output amps), and see what they might have available. It'll be spendy, as fuses go, but if it cures your difficulties.........
Roger
Roger