Is the audio going silent in your Chevrolet or GMC? We see the posts across our forums: the music drops out, the navigation goes quiet, and even the familiar turn signal click disappears. It is an incredibly frustrating experience when you just want to enjoy the drive in your premium vehicle. 

The good news is that General Motors is listening, tracking the root causes, and actively releasing solutions. In May 2026, GM updated a preliminary Technical Service Bulletin (PIT6406H) to help dealership technicians properly diagnose these audio complaints.

The issue boils down to a mix of software glitches and specific amplifier hardware anomalies. Here is a breakdown of what is happening behind the dashboard, what GM is doing to make it right, and how you can figure out which specific issue is plaguing your rig.

Is Your Vehicle Affected?

This diagnostic bulletin applies to vehicles equipped with the IOK radio system paired with specific audio options (look for RPO codes UQA, UQF, UQS, or NKD in your glovebox or door jamb sticker). The list of affected platforms is extensive:

The interior of a GMC Sierra Denali showing the digital dashboard and infotainment screen, illustrating the high-tech cabin affected by GM audio system bugs.
Your Denali interior is a high-tech sanctuary—until the audio drops out and your turn signals go silent. If you are experiencing a quiet cabin, it is time to determine if you are dealing with a software bug or a hardware fault.

The Two Types of Audio Gremlins

According to the bulletin, owners are generally bringing their vehicles into the service bay for one of two distinct conditions. GM handles each one very differently.

Condition 1: The Annoying Audio Skip

If your audio drops out for just 1 to 2 seconds at a time throughout your drive, GM has identified this strictly as a software anomaly. While it is certainly annoying to have your favorite song skip, the official instruction to dealerships is to avoid replacing the radio or the amplifier. GM engineering is actively developing a permanent software patch to cure the skipping. Replacing expensive hardware will not solve this specific bug, so owners will need to hang tight for the over-the-air update.

Condition 2: The Silent Cabin (Complete Audio Loss)

The more alarming symptom is a complete loss of audio for the duration of your drive cycle. You get zero sound from the speakers, and sometimes the audio magically returns the next time you fire up the engine. For this complete dropout, the fix depends heavily on your model year and the exact amplifier installed on the assembly line.

  • The Hardware Fix (2023 and 2024 Models): GM has narrowed down a specific batch of amplifiers prone to failure. If you own a 2023 or 2024 model with the UQA or UQS premium audio systems, the dealership will scan your vehicle to check the amplifier part number. If your part number matches the problematic batch (UQA: 85661488, 85661516, 86587284, 86587287 or UQS: 85661494, 85661517, 86587285, 86587288), the dealership will replace the amplifier entirely under warranty.
  • The Software Reset (2022, 2025, and 2026 Models): If your truck falls outside the 2023 or 2024 window, or if your amplifier part number is not on the suspect list, GM requires technicians to perform a “global reset” to see if the system recovers.

How to Test Your Own Truck

If you are currently dealing with a completely silent radio, you can figure out if you have a software bug or a dead hardware component before you even schedule a service appointment.

When the audio drops completely, perform a global reset (which can be as simple as safely disconnecting and reconnecting the battery).

  • If the audio comes back to life: Your truck is experiencing the known software anomaly. Just like the skipping issue, GM explicitly tells technicians not to replace the radio or amplifier in this scenario. You have verified your hardware is functioning, and you will just have to wait for GM engineering to finalize the software patch.
  • If the audio remains dead: You likely have a true hardware failure. The bulletin notes that if a global reset fails to bring the sound back, technicians must proceed with standard diagnostic procedures to find and replace the broken component.

Join the Conversation

Are you dealing with the audio skipping or a completely silent cabin? Head over to the community and share your experience to help other owners track this issue!