Woo Audio WA7d Fireflies Duo - Manual (Page 14)

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FAQ - Frequently Asked Questions
Computer cannot find the WA7d Fireflies Duo USB DAC.
o
Check USB cable connection and make sure the cable meets USB 2.0 specifications.
o
See “Macintosh with USB 3.0 running OS X 10.9 and later” for Apple Macintosh computers
o See “Installing USB driver” section for Windows PC
No sound is coming out of the headphone jack.
o
Check you have selected the correct position of the Input-Output switch. Check input connection.
Check computer USB output setting if USB input is used.
No sound is coming out of the mini headphone jack.
o
Only one headphone is operational at a time. Disconnect headphones from the ¼” jack to enable
output of the mini phone jack.
There is static noise, or one channel is dropping out.
o
Re-seat all tubes. Make sure that all tubes are securely installed.
The LED does not light.
First check if the AC cord is installed. Next, check if the umbilical cord is securely attached between the
amp and the power supply. If the fuse is burnt, see the following instruction on how to replace a fuse. The
fuse type is 400mA@115V or 200mA@230V, slow blow type (spare fuse included).
Mac OSX 10.9 does not recognize USB device
On some Macs with USB 3.0 running OS X Mavericks 10.9, WA7 and WA7d Fireflies can occasionally lose
connection to the Mac. If this has happened to you, please give the following a try.
- Use a good quality USB cable
- Disconnect all USB devices connected to your Mac
- Remove all audio plug-ins from Mac
- If you have Apple Cinema Display powering your MacBook via Thunderbolt, please disconnect as well.
With the Mac AND WA7d powered ON, disconnect the USB cable. Wait a few seconds.... reinsert the
USB cable. Next, following instruction on “Configuring Mac” section.
Lastly, try a powered USB hub like this Belkin (F4U040v)
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Insert a small flat
screwdriver into the
fuse door located on
the AC inlet.
Pull the fuse door
to open it.
The fuse holder
may be released
from the AC inlet. Replace the burnt
fuse with a new one
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