Cisco Cisco TelePresence MX700 Guía Del Usuario

D15029.01 Troubleshooting Guide TC6.0, April 2013. 

Copyright © 2013 Cisco Systems, Inc. All rights reserved. 

14

Audio problems

No sound locally

in audio issues like video you need to determine which site is having the problem. if you are not hearing 

the far-end site it could be an issue locally with your speakers or audio output or the remote sites 

microphone.

• 

Check the cabling if you are using external speakers.

• 

Check if your systems output is set correctly to the desired output (headphone, speakers or 

handset). This can be checked under 

.

• 

From the same screen you can check that 

Volume is set to a reasonable level. You can adjust 

the volume from the Touch panel, remote control or web interface.

• 

The far-end caller should check to ensure their microphone is not muted and check the physi-

cal connection of the microphone to ensure one is connected to their system. if your system 

or the far-end is muted you should see an onscreen graphic indicating this.

• 

You can test your system’s audio output by changing the ringtone from the Touch panel at 

 or remote control at 

. 

You should hear the ringtone from your selected output device (headset, handset or speakers).

• 

if you are using a system that uses a DNAM (profile, T1, T3) ensure the audio cable is 

connected to the codecs audio output and that the DNAM is detected (see next section No 

sound (DNAM) – profile, T1 and T3 Systems).

No sound (DNAM) – Profile, T1 and T3 Systems

The DNAM is a multichannel amplifier with digital signal processing built-in. it is a component specially 

designed for use with Cisco codecs.

• DNAM Short, used in profile 65, T1 and T3
• DNAM ii, used in profile 42, profile 52 and profile 52 dual
• DNAM iii, used in profile 42 MKii, profile 52 MKii and profile 52 dual MKii

NOTE

 The T3 DNAM setup is special. if you experience any problems with it, please contact support. 

• 

Make sure all cables are properly and correctly connected. This includes the rCA cable from 

the codec audio output to the DNAM input, the cable(s) from the DNAM to the loudspeaker 

drivers or monitor assembly, and the power cable to the DNAM. On some systems some 

of these connections are not easily available, check those that are available. Verify that the 

DNAM is connected to 

Line out 1 on the codec. Verify that the Line out 1 Type is set to Auto. 

You can find this in the audio part of the codec’s advanced configuration settings.

• 

power-cycle the complete system, including the codec, by pulling out and reinserting the 

mains plug from the wall socket. Wait for the system to boot completely and check the sound 

again. if cables and hardware are OK this will reset all software functions and re-establish 

codec-DNAM communication properly.

• 

if the problem persists, check the DNAM fuse. Make sure not to damage the fuse holder when 

removing the fuse for inspection. push the fuse holder slightly inwards and turn counter-

clockwise for release. On some systems this can be done with fingers only, on others a flat 

screwdriver is required. On some systems pulling the fuse holder out can be made easier by 

using a pair of pliers. if the fuse is blown it should be replaced with a 

Littelfuse 215002, which 

is a 2A 250V time-delay high-breaking capacity fuse. This should be readily available from 

electronics component warehouses. Some systems have an extra fuse kit in the column. Also 

inspect the fuse holder for damage. Take care also when reinserting the fuse and fuse holder. 

push slightly inwards and turn the holder carefully clockwise until it locks in place. 

NOTE 

Using 

different fuses may easily lead to repeated failures or more serious hardware malfunction.

• 

problem in codec, check settings and output signal, make sure there is sound.

• 

Try connecting external source to DNAM input.

• 

Check 

 to see that the DNAM is detected 

– Type=DigitalNAM. if the DNAM is detected, there may be errors with speaker iD and cabling, 

contact support for assistance. 

Troubleshooting Guide TC6.0