NAD 3103 burn out

[poundy]

Heres an interesting one

Had many of these go like this always the same and always R448 seems to be the weak link

but heres whats different about this one compared to the rest ive fixed

no blown fuses
no lamp on
and it still works, although a bit quieter than the other channel

question is:
why is it always the right channel that goes?

 

[rayma]

Maybe R448 is intended to burn to protect the rest of the circuit? If not, you could use
a higher power part there.

If the right channel really fails much more often, maybe the ventilation or the layout
is not as good as for the left channel.

 

[poundy]

I always replace this resistor with a 1/2w