No Sound / Audio Troubleshooting
This guide applies to BMW CarPlay & Android Auto retrofit interfaces including CIC, NBT and EVO systems.
Common Symptoms
• No sound from CarPlay or Android Auto
• Calls work but music does not
• Distorted audio
• Laggy audio
• Navigation prompts cannot be heard
• BMW chimes or vehicle sounds missing
Step 1 – Check AUX Source
The most common cause of no sound is AUX not being selected.
Please verify:
• AUX is selected within the BMW Media menu.
• AUX volume is not set to zero.
• We recommend setting AUX volume to approximately 10.
Step 2 – Check Bluetooth Configuration
BMW retrofit systems can operate using either:
Option A – BMW AUX Mode (Recommended)
• Audio routes through AUX.
• Most reliable configuration.
• Full CarPlay and Android Auto functionality available.
Option B – BMW Bluetooth Mode
If "Use Car's BT Channel" is enabled:
• Phone must be connected to the BMW Bluetooth.
• Phone must also be connected to the retrofit Bluetooth (EW-CPXXXXXX).
• Both connections are required for proper operation.
Step 3 – Check Phone Audio Settings
Verify:
• Media Audio is enabled.
• Bluetooth Audio is enabled.
• Volume is turned up on the phone.
• Volume is turned up within the BMW system.
Step 4 – Check Fibre Optic Connection
If your vehicle is equipped with a fibre optic cable (MOST system):
• Ensure it has been transferred from the original connector to the retrofit harness.
Common symptoms include:
• No sound
• Missing vehicle information
• Missing OEM audio functions
Step 5 – Audio Quality Issues
If sound quality is poor:
Navigate to:
Setup → Audio → EQ
Adjust the equaliser settings to suit your vehicle's audio system.
Step 6 – Restart The System
If changes do not take effect:
• Restart the vehicle.
• Hold the BACK button for approximately 10 seconds to restart the retrofit system.
• Re-test audio.
Still Need Assistance?
Please email support@bavarian-automotive.co.uk with:
• Order Number
• Vehicle Model & Year
• Photos of Wiring
• Photos of DIP Switch Settings
• Video Demonstrating The Issue
• Confirmation whether AUX or BMW Bluetooth Mode is being used
A member of our technical support team will review your case and respond via email.