Edirol USB Audio/MIDI Interface UA-20 User Manual

Troubleshooting

If a mic or guitar is connected to the UA-20, disconnect the mic or guitar, and turn the 
input sensitivity knob all the way to the left. 
Disconnect any audio devices you are not using.

If a USB-compatible MIDI sound module and the UA-20 are connected via USB to the 
same computer, and the outputs of the MIDI sound module are connected to the line 
input jacks of the UA-20, noise from your computer may be heard via the MIDI sound 
module from the UA-20, depending on the computer you are using. If this occurs, you 
can either connect the MIDI sound module and the UA-20 in parallel using a self-
powered hub, or connect the MIDI sound module via its serial or MIDI interface.

Try connecting only a single UA-20 unit, and check whether the noise disappears. If 
numerous audio devices are connected to a computer, noise may occur depending on 
your system. In such cases, connect only the UA-20 to your computer.

If your ASIO-compatible software does not support ASIO 2.0, it will not operate 
correctly if you use 

 or 

 as the ASIO 

driver.

In this case, select either 

 or 

 as the ASIO 

driver.

If your ASIO-compatible software does not support 24-bit audio input/output, it will 
not operate correctly if you select 

 or 

 as 

the ASIO driver. In this case, select either 

 or 

 as the ASIO driver.

Try connecting the UA-20 directly to the USB connector of the Macintosh itself.