Sunfire IV - Manual (Page 54)

User's Manual
54
APPENDIX
Your amplifi ers shut down often
Check the following:
• Make sure each speaker's average
impedance is not less than your
amplifi ers can safely handle.
• The amplifi ers have good ventila-
tion, no vents are covered.
• Try setting all the speakers to
Small, and let your subwoofers
handle the heavy bass.
• Check that the amplifi er power
output is a good match for your
speakers. If your speakers are
ineffi cient, consider using larger
power amplifi ers.
Reset procedure
The TGIV is a microprocessor
controlled device of great complexity.
Occasional power fl uctuations and
spikes may cause the TGIV to "lock
up" or act strangely. The TGIV can be
reset as follows.
Warning: the TGIV will be reset
to the factory defaults, and
will clear all memory. All your
stored OSD settings and Tuner
presets will be erased.
• On page 57, write down your
calibration settings, input settings,
Tuner presets, and any other set-
tings you have made.
• Press the power button to turn the
unit off, or turn it off from the wall
for a moment.
• Press and continue to hold down
the front panel Power button and
the Tone DOWN button at the
same time.
• The TGIV will power on and cycle
through the display. Keep holding
the buttons down until "Resetting
to Factory Defaults" appears in the
front panel display
• When the TGIV has been reset, it
will shut off.
• Turn the TGIV back on and it will
go to the default screen. It has now
been reset.
• If the TGIV has to be reset regu-
larly, you should invest in a good
quality AC line conditioner.
Updating fi rmware problems
• See page 51
• If you have a Palm Pilot™ or simi-
lar device with “HotSync™” or its
equivalent, you may need to dis-
able this software before proceed-
ing. This software ‘seizes’ control
of a serial port on your machine
and prevents the Sunfi re software
from accessing that port. Use an-
other port or disable HotSync.
• Check that the serial cable is con-
nected correctly between the TGIV
and your computer's serial port.
A Hum is heard in your speak ers
This problem is more than likely
caused by a “ground loop” in your sys-
tem, rather than a fault in the TGIV.
Follow these steps to isolate the main
cause of the hum, there may even be
more than one.
• Remember to turn off all compo-
nents in your system, including
the TGIV, before disconnecting or
con nect ing any cables.
• Disconnect the following items in
order, and check each time if the
hum has gone away:
• Disconnect all cables which come
from outside the room, such as
cable TV, satellite TV, or roof top
antennas. Make sure that they are
dis con nect ed where they fi rst enter
the room, so they are making no
con nec tion to the TGIV or the TV,
or any other component. If the hum
is caused by the cable TV line,
then you will need a “ground loop
iso la tor.” This is an inexpensive
device fi tted in line with the coaxial
cable feed. Con tact your ca ble
com pa ny or your Sun fi re Dealer for
as sis tance.
• Disconnect all connections from
the TGIV to your TV.
• Disconnect any component which
has a grounded power cord.
• If the hum persists, disconnect all
the source com po nents one at a
time from the back of the TGIV,
until you identify the prob lem.
• Ground loop isolators are available
for audio lines and video. Ask your
Sunfi re Dealer for assistance.
• Try moving the speaker cables
away from any power cords. Try
just one speaker, connecting it to
different channels and see if an
amplifi er channel is bad.
• If you are still having a problem,
remember that Sunfi re’s dealers
and technical support staff will as-
sist you.
Other causes of noise
• Speaker noise may also be caused
by in ter fer ence or noise on your
AC line. Make sure there are no
large ap pli anc es sharing the line,
or halogen lamps or light-dimming
Triac devices.
• Try connecting your system to an-
other AC socket on a sep a rate line.
• If the hum is heard from within the
TGIV and not through the speak-
ers, this may also be caused by
in ter fer ence on the AC or DC lines.
The power trans form ers may turn
this interference into an audible
noise. Internal hum can be made
worse by a shelf or cabinet reso-
nating, so try moving the TGIV to
another shelf.
• Try moving your components further
away from the TV, es pe cial ly if
you ever notice the screen has
changed color in the area closest
to the component.
• If you have very high effi ciency
speak ers, these may show up
noise which other speakers may
not.