38
Trouble shooting
Many problems have a simple cause and a correspondingly simple solution. The following section describes a few
difficulties you may encounter, and the measures you need to take to cure them. If you find it impossible to solve a
problem with the help of these notes please disconnect the unit from the mains and ask your authorised
specialist
dealer for advice.
Machine does not switch
on (blue LED does not light
up).
Cause 1:
Mains lead not plugged in correctly.
Remedy:
Check connection, push connector in firmly.
Cause 2:
Mains switch on the back panel not switched on.
Remedy:
Switch the mains switch on.
No output signal to the
loudspeakers; the screen
displays the message
“PROTECT” or
“OVERHEAT”
(PROTECTION circuit has
been triggered).
Cause 1:
The PROTECTION circuit has tripped due to overheating or overloading.
Remedy:
Reduce volume and wait for about 20 seconds. If the unit does not switch on
again automatically, it has become too hot and should be left switched off for a
few minutes to cool down.
Cause 2:
Short-circuit in the speaker leads, e. g. stray wire ends touching at the speaker
terminals, or mechanical damage to the cables.
Remedy:
Check speaker leads and terminals, twist wire ends together neatly, replace
damaged cables.
Cause 3:
Overloading due to poor earth contact.
Remedy:
Disconnect input cable and wait to see if the amplifier switches back on again;
if so, check the input lead and replace if necessary.
Unit switches off repeatedly
at fairly high volume levels.
Cause 1:
Overheating due to heat build-up.
Remedy:
Set up the unit in such a way that an unobstructed flow of cooling air is guaranteed.
Cause 2:
Overheating through insufficient loudspeaker impedance.
Remedy:
Use only loudspeakers of at least 4
Ω
impedance (DIN rating). That means a
minimum impedance of > 3.2
Ω
.
Flat
sound
image,
insufficient bass response.
Cause:
The loudspeaker cables are connected with reversed polarity.
Remedy:
Check the speaker connections at the loudspeakers and at the amplifier’s
speaker terminals; correct if necessary.
Device switches itself off
automatically. Switching on
again
causes
the
the
machine to switch off again
Cause:
Extreme overheating, or short-circuit at the loudspeaker outputs.
Remedy:
Check for possible short-circuits at the loudspeaker terminals and leads. Allow the
machine to cool down for about twenty minutes, then attempt to switch it on again. If
this is still unsuccessful, an internal fault could be present (e.g. blown fuse). In this case
please contact your specialist
dealer.
Loud humming noise from
the loudspeakers.
Cause:
Poor contact between the Cinch plugs and sockets, or a faulty Cinch cable.
Remedy:
Please check all connections and cables thoroughly.
