[Jack[_11_]]

After a week of playing with no problems, the right channel went out. It
was the left channel previously. I was dismayed until I remembered that,
when I reseated the output trannies, I switch them, left for right. I
was further heartened when that same trick of switching off the speakers
and turning the volume up to max brought the sound back. Since there are
a pair of outputs in each channel, switching one of them again and
waiting to see which channel goes out next should tell me which tranny
is bad.