jvc av 27920 a 67 chassis loss of sound

[keith]

good day all
this set had vert probs originally. i repaired that and lost the
sound. now i had another one with the same vert prob. i repaired that
but the sound was ok. so i swapped the sound ics mts process ic 651
from the good set with sound to the one without sound. now i have no
sound on either set. i replaced the ic from the set with good sound
back to the original and still have no sound. does anyone know whats
going on here.
tks keith