This (old) stereo system works fine when using Tuner, Tape or Phono.
The problem is when using the CD player which has an Optical link
only. (Link is established correctly as shown by flashing indicator
turns steady after 4 seconds of disk operation)
The sound of the CD player can only be heard very very weak from
headphone or speakers. (Volume rotated to max.CW)

Using some basic troubleshooting technique by probing with the
oscilloscope,I have established that the CD signal gets thru the
optical link unattenuated. It is DA converted somewhere and I have
noted the presence of good analog audio levels at two Caps (Left &
Right audio present)..

It looks like that the audio is not switched correctly/completely to
the Final Audio amp. (permanent mute ?)

Normally some digital IC will do that job, but not having the AKAI
schematic I have been unable to trace its circuits.

Anybody who can help ?

TY
Brasto