Troubleshooting - Universal Audio Apollo x4 Hardware Manual

Troubleshooting

If Apollo x4 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 DAW
playback
Undesirable echo/phasing
Static and/or white noise
is heard when nothing is
plugged in
Various LEDs inside the
unit are blinking
Apollo x4 is behaving
unexpectedly
Apollo x4 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 Thunderbolt 3 cable is fully inserted at both ends
• Confirm the newest Apollo x4 software is installed (reinstall if necessary)
• Power off system, power on Apollo x4, then start computer
• Try a different Thunderbolt 3 cable
• Confirm connections, power, and volume of monitoring system
• Confirm Apollo x4 monitor level is turned up
• Confirm monitor outputs are not muted (push MUTE button when in Monitor mode)
• Confirm monitor output LEDs are active (check signal flows)
• Confirm mic/line select switch setting is correct for the channel (CH1/CH2/CH3/CH4)
• Confirm mic/line setting matches the input plug for the channel (XLR or ¼")
• Confirm preamp gain is turned up for the channel(s)
• For channels 1 and 2, confirm nothing is plugged into its 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 plug is 1/4" mono TS (TRS cables cannot be used with Hi-Z input)
• Confirm desired channel is selected for control
(push PREAMP button repeatedly to select CH1/CH2/CH3/CH4)
• 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 I/O Hardware Buffer (Mac: in DAW settings; Windows: in Console settings)
• 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
• Disable software input monitoring if monitoring via Console (recommended)
• Mute all Console inputs if software input monitoring via 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 x4
2. Press and hold the PREAMP, FILTER, and POLARITY buttons
3. Power on Apollo x4 while continuing to hold all three controls
4. After all front panel LEDs flash rapidly for several seconds, release the controls
ITEMS TO CHECK
35 Troubleshooting