Yamaha ACU16-C, NHB32-C

36 Troubleshooting

ACU16-C & NHB32-C Owner’s Manual

Troubleshooting

Unit Symptom Advice

ACU16-C

NHB32-C

Cannot power up?

Make sure that the power cord is connected to a suitable AC wall outlet. Also

make sure that the other end of the power cord is connected to the unit’s AC IN

correctly. Use the supplied retaining clamp to ensure that the power cord cannot

be disconnected inadvertently. Make sure that the POWER switch is set to the ON

position. If you still cannot turn on the unit, contact your Yamaha dealer.

Cannot establish a

connection with

NetworkAmp Manager?

Make sure the unit is powered up and that NetworkAmp Manager is running

properly on your PC.

Have you installed the necessary Yamaha USB or CBX driver? See “NetworkAmp

Manager Installation” on page 10.

In NetworkAmp Manager, choose General Setup from the Option menu and

make sure that the correct MIDI driver is selected. If you are using a USB connec-

tion, this should be “YAMAHA USB.” If you are using an RS-232C serial connec-

tion, it should be “YAMAHA CBX Driver.”

If you have used NetworkAmp Manager with a USB connection, while the USB

cable is still connected, even if you select the “Yamaha CBX Driver,” a serial con-

nection will not work unless the USB cable is disconnected.

Check the USB or RS-232C serial cable connections as appropriate. If you are con-

necting to an NHB32-C, be sure to connect to the TO COMPUTER port, not the

COM port.

If you are using a USB connection, make sure that your PC’s USB port is working

correctly. In Windows, open the System control panel and click the Device man-

ager tab. See your Windows documentation for further information.

If you are using an RS-232C serial connection, make sure that your PC’s serial

port is working correctly. In Windows, open the System control panel and click the

Device manager tab. See your Windows documentation for further information.

Make sure that all ACU16-Cs and NHB32-Cs are assigned exclusive unit IDs. It’s

okay to use the same unit IDs for ACU16-Cs and NHB32-Cs.

Connected the unit to a

CobraNet network and

the CONDUCT and

ERROR indicators light

instead of the LINK

indicator?

Make sure that all devices on the network are powered up.

Make sure that the Ethernet cables are connected to the unit properly (i.e., check

they’re not pushed in only half way).

Try swapping the Ethernet cable with a known good cable.

Try connecting the unit to another port on the hub.

Try disconnecting other devices from the network one-by-one to determine if

another device or Ethernet cable is at fault. CAT3 Ethernet cable will almost cer-

tainly cause problems, as will incorrectly wired cables, damaged cables, cables

deformed by tight cable ties, and tightly bent cables. When making cables your-

self, be sure to maintain the natural twist of the conductors as close to the connec-

tor as possible. More than 25 mm of untwisted cable can affect performance.

The LINK indicator is lit,

but digital audio cannot

be transmitted or

received?

Make sure that your CobraNet devices are set to transmit and receive the correct

bundles. Also check your audio connections, audio sources, and audio I/O to bun-

dle assignments.

The CONDUCT

indicator never lights

up?

This is normal. The CONDUCT indicator lights up only when the unit is working as

CobraNet conductor. This selection is made automatically and you don’t normally

need to do anything.

The ERROR and

CONDUCT indicators

light simultaneously?

A CobraNet link cannot be established. Make sure that the switching hubs and

other devices are properly connected and turned on.

The LINK, CONDUCT,

and ERROR indicators

ﬂash simultaneously?

A system error has occurred. There maybe an incorrect setting on another device

or the unit maybe faulty. See “System Errors” on page 37 for more information.

The ERROR indicator

ﬂashes?

An error has occurred with the unit’s built-in CobraNet interface. Check the cable

connections and settings of all devices on the network. If you cannot resolve the

problem and the ERROR indicator keeps ﬂashing, the unit maybe faulty, in which

case you should contact your Yamaha dealer.

Audio sounds distorted?

Continuously distorted sound is most likely due to overloaded audio inputs and

levels being too high. Intermittent audio clicks and pops may be network related.

Check your Ethernet cables and other CobraNet devices. Also check your word-

clock settings.