C.E.C. TUBE53 Owner's Manual page 17

If you suspect a malfunction in the unit, please check the following chart
before calling your dealer.
No power
Check the connection at the both ends of the AC power cord. Make sure there is power at
the wall outlet.
Replace the fuse at the AC inlet if it is broken.
No sound
Check the connection from the external source device (e.g. CD player).
Check the operation of the external source device (e.g. CD player).
Turn the unit off and unplug the AC power cord from the outlet. Wait for a minute before
plugging the AC power cord back in and turning the unit back on.
Noise on sound
Check that the interconnect cables are plugged in adequately.
Replace any broken vacuum tubes.
17