JBL AV2 User Manual - page 75
JBL
®
Performance™ Series AV2 Audio/Video Processor
Troubleshooting and Maintenance
6-3
A humming sound is present in the audio.
1. If a cable TV connection is present, disconnect the cable from
the wall outlet. If this eliminates the humming sound, a ground
loop isolation device is required. Contact your dealer or cable
provider for assistance.
2. Disconnect components one at a time to isolate the problem.
Once the problem is identified, make sure the associated
component is properly grounded and connected to the same
electrical circuit as the AV2 processor.
RF interference is present in the audio or video.
1. Make sure the AV2 is not positioned too close to RF-emitting
devices.
2. Move such items one at a time to isolate which device is
causing the problem.
3. Replace unshielded cables with shielded cables wherever
possible.
Audio sounds are distorted when using analog audio inputs.
The likely cause for distorted audio while using the analog audio
inputs is that the input voltage is too high. The AV2 analog inputs
have a maximum rating of 2 Vrms. Any input voltages higher than
this limit will exhibit audible distortion.
To correct the problem, reduce the analog audio output from the
connected device using the volume or level control. If neither is
available, an intermediate device may be required. Contact your
JBL dealer for assistance.
In the SEMI AUTOCAL Test, the Far Field Test keeps failing.
1. Ensure that the microphone is placed in your preferred seating
location.
2. Ensure that the volume is set to –20dB.
3. In the Speakers menu, ensure that none of the speakers
connected to the system have a crossover selection of NONE.
During the Far Field Test, test tones are sent to ALL speaker
locations, regardless of the settings identified in the Speakers
menu. Therefore, every speaker that is plugged in MUST have a
crossover setting other than NONE for the Far Field test to be
successful. If a crossover is set to NONE but the speaker is
plugged in, the test will fail because it will “see” a speaker that
is identified as having no crossover point.
4. Refer to the “AUTOCAL Error Messages” section found later in
this chapter for more information about specific error messages
related to the AUTOCAL process.
The volume won’t go to the +10dB maximum level.
The speaker output level settings may affect the maximum volume
level of the AV2 processor. The maximum volume level is +10dB
minus the maximum output level setting of any speaker. Thus, if
your front L/R output levels are set to +3dB, the maximum
allowable volume level is +10dB minus 3dB, or +7dB.
The picture on the video monitor is all one color.
This is a synchronization problem when using an HDMI
connection. When the source device and video monitor do not
sync correctly, the color spacing may not load correctly. When
the monitor color is all red, or all green, it means that only half
of the color spacing data was loaded into the video monitor.
To correct the problem, simply enter the OSD menu and then exit
out again. This will resync the video and should clear the error.