Troubleshooting Audio

This guide will help you diagnose and fix common audio issues quickly, so you can get back to a smooth service.

1. General Troubleshooting Philosophy

Keep these core ideas in mind when things go wrong:

• Start Simple! Always check the most obvious things first. Is it plugged in? Is it turned on?
• Check the Chain! Sound travels like a chain: Microphone > Cable > Mixer Input > Mixer Fader > Mixer Output > Speaker. If one link is broken, the sound stops. Follow this path.
• One Thing at a Time! When trying to solve an issue, change only one setting or check one thing at a time. Then test. This helps you figure out what's actually fixing the problem (or making it worse!).
• Visual Check: Look closely! Are lights on that should be? Are cables fully inserted? Is there any visible damage?

2. "No Sound at All!" (The Big One)

This is the ultimate problem, but often the easiest to fix with a systematic approach.

1. Power Checks (Everything On?):

   • Is the Mixer (SQ7) ON? (Check the screen and power button light).
   • Are all Amplifiers ON? (Check the Crown amp for the Cryroom, and the BOSE wedge amp. Look for power lights on them).
   • Are the FOH Speakers ON? (Our EAW line array should have power lights, on the back). Double check all 4 switches on the power points are turned on.
   • Are the Wireless Mic Receivers ON? (Look for power lights in the rack - these should turn on automatically).
   • Are all power cables securely plugged into outlets and devices?

2. System Mutes:

   • Master Mute: On the mixer, check if the Main Output (LR) is muted. There's a dedicated mute button near the main fader. If it's lit, press it to unmute.
   • DCA Mutes: Are any of the DCA faders (Drums, Keys....Vox, Radios) muted? If, for example, DCA 7 (Vocals) is muted, you won't hear any vocal mics.
   • Channel Mutes: Is the individual channel you're trying to use muted? (Each channel fader has a mute button, often lit in red when active).

3. Signal Path Check (Follow the Chain!):

   • Is the Microphone/Instrument On? (For wireless mics, is the mic itself powered on? For instruments, are they plugged in and powered?)
   • Is the Cable Plugged In Firmly?
     • At the microphone/instrument end?
     • At the stagebox input?
     • Visually inspect the cable for damage. Try wiggling it gently at the connectors – if the sound cuts in and out, the cable is likely bad.
   • Is the Channel Gain Turned Up? (See Getting Started, Section 5A. Is the meter showing signal?)
   • Is the Channel Fader Up? (Push it up slowly).
   • Is the DCA Fader (if applicable) Up? (E.g., if it's a vocal mic, is DCA 7 up?)
   • Is the Main Fader Up? (Located near the right side of the mixer).
   • Is the Amplifier On and Receiving Signal? (Look for signal lights on the amp. If the amp has "protect" lights, it might be overheating or detecting a fault. Turn it off, wait, and try again).
   • Are Speakers Connected to Amplifiers? (For the Cry-room or BOSE wedge, ensure the speaker cables are firmly connected at both the amp and speaker).

4. "Isolate the Problem":

   • Try a different cable: If a mic isn't working, swap its cable with a known working one.
   • Try a different channel: Plug the problematic mic/instrument into a different, unused channel on the mixer. If it works there, the original mixer channel might be faulty.
   • Try a different microphone: If it's a wired mic, try another one. If it's a wireless mic, try another wireless mic in the same system.

3. "Sound is Too Quiet / Too Loud / Distorted"

1. Gain Staging Check:
   • Go back to the Gain knob for the offending channel (Getting Started, Section 5A).
   • Ask the person to deliver sound at their normal level.
   • Too Quiet: Slowly increase the Gain until the meter consistently hits yellow, just flicking into red.
   • Too Loud/Distorted: If the "Clip" light is constantly red, the gain is too high! Turn it down immediately until it's just hitting yellow.
2. Faders:
   • Channel Faders: Are individual channel faders at a reasonable level?
   • DCA Faders: Are the group DCA faders controlling many channels too high or too low?
   • Main Fader: This controls the overall volume. Ensure it's not too high or too low.
3. External Volume Knobs: If playing from a laptop or phone, is its own volume turned up or down too much?

4. "Feedback! (Squealing/Ringing Sound)"

Explanation: This happens when sound from a speaker gets picked up by a microphone, amplified by the mixer, and sent back out to the speaker, creating a loop that gets louder and louder.

Immediate Action:

• Quickly turn down the offending microphone's fader (or its DCA fader).
• If you can't tell which mic it is, lower the Main Fader until the feedback stops.

Long-Term Solutions:

• Move the Microphone: The simplest fix is to move the microphone further away from any speakers (especially the FOH speakers and monitor wedges).
• Don't Point Mics at Speakers: Ensure wired and wireless microphones are never pointed directly at a speaker.
• Reduce Microphone Gain: Lowering the Gain knob for that specific microphone can help, but don't lower it so much that the sound becomes too quiet.
• Use EQ to "Ring Out" Problem Frequencies: If feedback is persistent, sometimes specific frequencies are the culprit. On the mixer, you can gently reduce the mid-range (EQ) for that microphone, which is often where feedback occurs. (Use this with caution, as it can affect vocal tone).

5. "Microphone Isn't Working (But Others Are)"

A. Wireless Mic Troubleshooting (Sennheiser)

1. Battery Check: Are the batteries in the wireless microphone fully charged? (Check the mic's display for battery level). Change them if very low, or swap with a fully charged mic from the charge station. They tend to only have 2 bars of charge shown when taken off the charger. This is normal.
2. Mic On/Off: Is the wireless microphone itself powered ON?
3. Receiver On/Off: Is the corresponding wireless receiver in the rack powered ON? These should turn on automatically, but it's worth double checking.
4. Frequency Issues: While rare with our system, sometimes interference can cause dropouts. Ensure the mic and receiver are tuned to the correct frequency. (This is usually pre-set, but if problems persist, report to the head of AV.).
   • Look at receivers: Do they show signal? If not, try re-powering the mic.

B. Wired Mic Troubleshooting

1. Cable Swap: Immediately swap the microphone's cable with a known good cable. Many problems are simply due to a bad cable.
2. Try a Different Channel: Plug the wired microphone into a different, unused input channel on the mixer. If it works there, the original channel might have an issue.
3. Phantom Power Check: If it's a condenser microphone, ensure 48V (Phantom Power) is activated for that specific channel on the mixer.

6. "Intermittent Sound / Crackling Noise"

1. Loose Connections: This is the most common cause. Wiggle every cable (gently!) at both ends, from the mic/instrument to the stagebox, to the mixer. See if the crackling stops or changes. Re-seat any loose cables by unplugging and plugging them back in firmly.
2. Damaged Cables: Visually inspect cables for frayed wires, bent pins, or exposed copper. Replace any suspicious cables.
3. Power Issues: Is the power cable to a device inserted correctly, loose connections can cause issues.
4. Interference (Wireless Mics): Strong radio signals or electrical interference can cause crackling in wireless systems. Move the mic if possible.

7. "Monitors Not Working / Not Getting Enough Sound"

This applies to both wired/wireless IEMs and the foldback wedges.

1. Recall 'Church Standard' Scene: First, reload the "Church Standard" scene to ensure basic routing is correct.
2. Check Aux Send Levels (Individual Channels):
   • For the person who can't hear, select their microphone channel on the mixer.
   • Go to the "Aux Sends" section for that channel.
   • Check their specific Aux Send knob/fader (e.g., AUX 9 for Worship Leader's wedge, AUX 5 for Wired Drum IEM) and ensure it's turned up for their mic.
3. Check Aux Master Fader:
   • Switch the mixer to Layer F (Outputs).
   • Locate the master fader for their specific Aux output (e.g., AUX 9 Master, AUX 5 Master). Make sure this fader is up! This controls the overall volume for that entire monitor mix.
4. Is the IEM Pack On / Wired IEM Mixer On?
   • Wireless IEM Pack: Is the Sennheiser pack powered on and charged? Is the volume knob (on the pack itself) turned up?
   • Wired IEM Mixer (Drums - ZED-6 mixer): Is the small mixer powered on? Are its input/output volumes up?
   • Wired IEM Amplifiers (Bass, Keys): Is the amplifier turned on?
5. Foldback Wedge Power & Connections:
   • Powered Wedge (Worship Leader): Is the wedge itself powered on?
   • BOSE Wedge: Is its separate amplifier powered on? Are the speaker cables connected firmly?

8. "Aux Input Device (Laptop/Phone) Not Playing"

1. Playing on Device? Is the actual laptop/phone playing the audio? Is its own volume turned up?
2. Right Cable? Is the correct cable connected from the device's headphone output to the "Mac Audio" input on the mixer?
3. Input Selected: Is the correct input channel (e.g., "Mac Audio") active on the mixer?
4. Mixer Faders Up? Is the individual channel fader for "Mac Audio" up, and is DCA 8 (Other Audio) up?

9. "Help! I Still Can't Fix It!" (Escalation)

If you've tried everything above and you're still stuck, don't worry! Sometimes problems require more in-depth knowledge.

1. Contact:
   • Immediately inform our head of AV or the Worship Pastor.
   • If no one is immediately available, please leave a clear note for the next person or try to call them.
2. What Information to Provide:
   • The Problem: Clearly describe what's happening (e.g., "No sound from the worship leader's mic," "Loud hum from the main speakers").
   • What You Tried: List the troubleshooting steps you've already attempted (e.g., "Checked power, swapped cables, tried a different channel"). This saves time!
   • What Equipment is Involved: Specify which microphone, speaker, or section of the mixer seems to be causing the issue.

Your effort in checking these steps is a huge help to the entire team and keeps our services running smoothly! Thank you for your dedication!