LAMTTO Carplay Screen Audio Issues: Complete Fix Guide (2026)

LAMTTO RC series wireless CarPlay devices support three audio output methods:

• FM Transmitter
• AUX Cable
• Bluetooth (Best Sound Quality)

Audio stability is critical for navigation prompts, calls, and music playback.

However, some users may experience issues such as:

• Static noise
• No sound during calls
• Bluetooth audio not working
• Audio delay

👉 The good news: Most audio issues can be fixed in minutes.

This guide covers all common audio problems and step-by-step solutions for LAMTTO RC devices.

🎧 1. Audio Output Methods Explained

FM Transmitter

• Set a frequency on the device (e.g., FM 106.0 MHz)
• Tune your car radio to the same frequency
• Audio plays through your car speakers

⚠️ Important:
The FM antenna is built into the original car charger. Always use the original charger.

AUX Cable

• Connect the device AUX port to your car AUX input
• Direct wired audio transmission

Bluetooth (Recommended)

• Select BT output mode on the device
• Connect your phone to the car’s Bluetooth

👉 This provides the best sound quality

📻 2. FM Static Noise / Interference

Problem

Buzzing or static noise when using FM mode.

Fixes

• Use the original car charger (critical)
• Keep cables away from the car radio
• Change FM frequency (e.g., 87.5 → 106.0)
• Switch to AUX or Bluetooth
• If unresolved, contact support (compensation may apply)

🔌 3. AUX Noise / Humming Sound

Problem

Buzzing or humming sound via AUX.

Fixes

• Reinsert AUX cable securely
• Check correct AUX port
• Try another AUX cable
• Use a ground loop isolator
• Switch to Bluetooth or FM

👉 If still unresolved, AUX port may be defective

Why This Happens

• Ground loop interference
• Electrical noise from car electronics

📞 4. Cannot Hear Caller (iPhone)

Problem

You receive calls but cannot hear the other person.

Fixes

• Check audio output → select CarPlay
• Tap Speaker (Audio output switch) during call

📞 5. Cannot Hear Caller (Android)

Fixes

• Check mute settings
• Test voice assistant
• Switch to Bluetooth audio mode

🎤 6. Caller Cannot Hear You

Problem

Your voice is not heard or too quiet.

Fixes

• Use Bluetooth output (recommended)
• Close windows to reduce noise
• Ensure voice input is enabled
• Check phone audio output settings

👉 If still not working → possible hardware issue

🔁 7. Echo During Calls

Problem

Echo during phone calls.

Fixes

• Lower call volume
• Restart device and phone
• Update phone system
• Switch to Bluetooth mode
• Test call without CarPlay

🔊 8. Bluetooth Audio Not Working

Problem

No sound in BT mode.

Fixes

• Restart phone
• Ensure correct connection order:
• Select BT mode on device
• Then connect phone to car Bluetooth
• Test car Bluetooth independently
• Check if car supports audio (not just calls)
• Check volume settings

🎙️ 9. Siri Not Working via Bluetooth

Fixes

• Reset Bluetooth connections
• Reconnect devices
• Restart phone and device
• Test Siri directly via car Bluetooth
• Update system

🔉 10. Device Still Produces Sound (AUX Mode)

Problem

Sound comes from both device and car.

Fixes

• Ensure output set to AUX
• Reinsert AUX cable
• Try another cable

⏱️ 11. Audio Delay / Call Lag

Problem

Navigation or calls are delayed.

Fixes

• Restart phone and device
• Close background apps
• Reset Bluetooth
• Try another phone

🔄 12. Why Bluetooth Disconnects After Connecting

👉 This is normal behavior

How It Works:

• Bluetooth is used for pairing
• Wi-Fi handles data transmission
• Bluetooth disconnects afterward

Bluetooth Output Mode Explanation

When using BT mode:

👉 Audio path becomes:
Phone → Car Bluetooth → Speakers

📺 13. AirPlay Disables Bluetooth Audio

Problem

Bluetooth audio stops during AirPlay.

Explanation

AirPlay and Bluetooth are mutually exclusive.

👉 Use AUX or FM during screen mirroring

🚗 14. Music Works but Calls Don’t

Problem

Music plays, but calls don’t go through car speakers.

Why It Happens

Some cars only support one active call audio (HFP) connection.

Fixes

• Delete phone Bluetooth pairing
• Reconnect cleanly
• Ensure no other devices are connected

🚀 Final Thoughts

Most LAMTTO RC audio issues are caused by:

• Incorrect output settings
• Interference (FM / AUX)
• Bluetooth conflicts
• Vehicle compatibility

👉 With the solutions above, you can fix almost all audio problems quickly.

💡 Pro Tips

• Always use the original charger (for FM stability)
• Use Bluetooth mode for best audio quality
• Keep your phone system updated

Need Help?

If the issue persists:
👉 Contact our support team: support@lamtto.com for technical assistance or replacement