Yes i replace that fluse fl231 all the time at the shop. at least two aweek. and the first few i replaced did the same thing. I would send it back to customer and i would get a call that the set had malfuctioned again and convergence gone. It was determined the reason this fuse blows is bad conections on the flyback transformer. The flyback is the big black component with the red wire coming out of the top. if you examine the connections on this component there will more than likely be a ring in the solder. this is caused by the manufacturing process known as LEAD-free solder. THis cause oscillations in that cuicit. like turning it of and on really fast. this is a very small fuse and cant stand up to this. so when you replace this fuse just simply RESolder these connections apply a little amount of solder to these connection. i am confident this will fix your problem.

The problem is related to the Convergence power supply board, which is shorting out and blowing fuse FL231. You will need a new Convergence power supply board to repair the Issue with the ITC222 chassis. You can get a replacement board at the following link.
http://servicemanuals.vstore.ca/