Classe ten amp and Thiel CS 1.6 speakers

Hello,
I am current have 2 Classe Ten using to drive 2 magnepan 1.4 as mono block. I want to switch to use these 2 amps for my Thiel CS 1.6.
My system:
Maranzt CD player.
Hamakardon AVR25II (using as a preamp)
Classe Ten amp
Thiel CS 1.6

1/First set up
Use exactly current connects for magnepan mono from Classe amp(mono mode).
After playing about 2 hrs the left speaker went lower volume. I tried balance knot on Preamp to balance the volume from left and right then the left amp fuse is blew.

2/Sencond set up

I tried just one Classe Ten (stereo mode) for Thiel CS 1.6. First everything looks OK. I can fell the amp still really powerful. After 3 hrs run everything still OK. I turn system off. The next day I turned them on I found out the amp's fuse is blew again.

I'm confused and don't really know what happen.

All advices will be appreciated,

Dave