Chapter 5: Troubleshooting - Universal Audio Apollo Twin Hardware Manual

Chapter 5: Troubleshooting

If Apollo Twin USB isn't behaving as expected, some common troubleshooting items
to confirm are below. If you are still experiencing issues after performing these checks,
contact Technical Support.
SYMPTOM
Unit won't power on
Unit is not recognized by
computer
No monitor output
Can't hear mic or line
input(s)
Can't hear mic input(s)
Can't hear Hi-Z input
Preamp controls have no
effect on channel
Can't adjust digital input
levels
Audio glitches and/or
dropouts during playback
Undesirable echo/phasing
Static and/or white noise
is heard when nothing is
plugged in
Various LEDs inside the unit
are blinking
Apollo Twin USB is
behaving unexpectedly
Apollo Twin USB Hardware Manual
• Confirm power supply connector is fully inserted, then twist barrel to lock
• Confirm Power switch is in "ON" position
• Confirm AC power is available at wall socket by plugging in a different device
• Confirm USB 3 SuperSpeed cable is fully inserted at both ends
• Confirm latest Apollo Twin USB software is installed (reinstall if necessary)
• Power down system, power on Apollo Twin USB, then start computer
• Try a different USB 3 SuperSpeed cable (USB 2 cables cannot be used)
• Confirm connections, power, and volume of monitoring system
• Confirm Apollo Twin USB monitor level is turned up
• Confirm monitor outputs are not muted (push level knob when in monitor mode)
• Confirm monitor LEDs are active (check signal flows)
• Confirm mic/line switch setting is correct for the channel
• Confirm preamp gain is turned up for the channel(s)
• On channel 1, confirm nothing is plugged into the Hi-Z input
• Confirm +48V phantom power is enabled if required by microphone
• Confirm volume on connected device is turned up
• Confirm Hi-Z input cable is 1/4" TS (TRS cables cannot be used with Hi-Z input)
• Confirm desired channel is selected for control
(push level knob to select channel when in PREAMP mode)
• Signal levels for digital inputs are adjusted at the device connected to those inputs
• UAD plug-ins can be used to add signal gain if desired
• Increase Hardware Buffer value in Console Settings>Hardware panel
• If syncing to external digital clock via optical input, confirm clocking setups
(confirm optical cable connections, matching sample rates, and that all devices are
synchronized to one master clock device)
• Confirm input monitoring is not enabled in both Console and DAW
• Mute or lower preamp gain to minimum on unused preamp channels
(mic preamps can emit noise even when nothing is plugged in)
• Some UAD plug-ins model the noise characteristics of the original equipment
(Defeat the noise model in the UAD plug-in interface, or mute the channel
containing the plug-in to temporarily mute the noise)
• This is normal operational behavior and can be safely ignored
• As a last resort, perform a hardware reset on the unit by following these steps:
1. Power off Apollo Twin USB
2. Press and hold the LEVEL KNOB, LOW CUT, and POLARITY controls
3. Power on Apollo Twin USB while continuing to hold all three controls
4. After all front panel LEDs flash rapidly for several seconds, release the controls
30
ITEMS TO CHECK
Chapter 5: Troubleshooting