Why did my amp just crash and burn ?

Yes the fuses are generic. Your manual should have the Info on the fuse value. Be sure you find out if you need slow blow or fast blow.

@chaseton 

Nothing wrong with the cables. Replace the fuse and carry on. Hopefully that is as far as it went.

Hopefully it is just a blown fuse.

However the hissing sound may be a symptom of a larger problem.  It could also be just a coincidence it coincided with the cable swap.

I can elaborate more, if a fuse swap doesn't fix the problem.

@ozzy62 

Looking at the YBA YA201 manual :

Fuse - 6 A ( versions 110v and 117v)

ou 3.15 A (versions 230v)

I will try and open the small drawer compartment above the power cord later today.

Btw, just spoke with the tech dept at AQ, ITO, applying the left cable to the right channel and vice versa should not have any attendant issues. Sound will just be transposed in the process. They believe it might just have been a power spike or surge last night, which is possible. As for the cables, the chances they were damaged would be quite low. Although , as we are finding anything is possible with audio system setup.

@blackdoghifi I would value your advice if  the fuse does not fix the problem. 

Hey, you may have a short.  Disconnect the cables from both ends and measure the resistance, should be infinite. Check for even the thinnest of stray copper threads.