Diamond Dave

Suddenly started to notice that every time I install a new proper rated/style fuse in and power up sub that it ends up blowing right away. Has anyone heard of this being a common issue on these early/mid 2000s year amps? What is the common failure and good repair to get it working again?

Any ideas on the original amp and why it started blowing fuses as soon as it's powered up? Have you seen a common failure causing this to happen from a certain area/component on these amps? Money is extremely tight so I'm thinking I need to take a whack at it myself first but if I can't do you think we are talking approx $60. cost as well?