No Sound from infotainment center or turn signals... HELP (Resolved)

[echo_mtn]

Also, I've noticed a pattern with mine that may or may not be a real thing, but after doing what I described below, I've not had any loss of audio in the last 2.5 weeks (knock on wood).

I've noticed a strong correlation between leaving CarPlay open on the screen when shutting off the truck and losing audio completely the next time I start it up. The infotainment system will try to bring up CarPlay again automatically (presumably since it's stored in memory that I had it open) - the carplay screen will show up right after the GMC logo displays up, and I always notice it because of the little "zoom" effect that the CarPlay icons do when it boots up. In fact, that eventually became my signal for knowing "aw, crap, audio's not gonna work now."

I've consciously tried to make sure that I'm not in the CarPlay app and that I'm looking at the main menu of the GMC infotainment when I turn off the truck and get out, and that seems to be making a difference. I'm curious if any others might have the same experience. Of course, now that I said that, I'll go out to my truck this evening to head home and the audio won't work

There might be some settings I can play around with under the hood to ensure that CarPlay doesn't automatically start on power up, but I haven't explored that far yet.

 

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[kevinwatson5]

Thanks for the update - sorry there wasn't better news.

That document you showed is the PIT6406A service bulletin that I linked to previously in the thread - and yeah, it shows that only the 2023 and 2024 model years with those part numbers are the ones that will get swapped out... which seems super weird to me. What they have on their hands definitely feels like a software issue, so I don't know why they selectively want to swap out hardware on the 2023-2024 models. Must be trying to fix a different or slightly-related issue. Ironically, my brother-in-law's 2024 AT4 has done this audio thing to him ZERO times... go figure.

I am in the same boat, my buddy bought one, same year and model, just has vs diesel and zero issues. I have had 3 to 5 issues per month in the first three months of ownership.

 

[Jbird]

It’s certainly annoying and erratic behavior. And it seems to happen more when I read/post this thread.

 

[echo_mtn]

It’s certainly annoying and erratic behavior. And it seems to happen more when I read/post this thread.

Haha! We should all just go silent for a month and enjoy problem-free operation, then.

 

[Renegade24]

Oh man I just bought a Denali Ultimate 2500 HD less than a month ago and I too am experiencing the no noise blinker and lost audio. Extremely frustrating because i love the truck but absolutely cannot go without music.
I would have hoped they had this solved already, my truck was built in May 2025. So can i ask you guys how long the dealership had your trucks while fixing this issue?

 

[gemarsh]

Oh man I just bought a Denali Ultimate 2500 HD less than a month ago and I too am experiencing the no noise blinker and lost audio. Extremely frustrating because i love the truck but absolutely cannot go without music.
I would have hoped they had this solved already, my truck was built in May 2025. So can i ask you guys how long the dealership had your trucks while fixing this issue?

Welcome.

 

[Renegade24]

Thank you and so glad I found this thread

 

[BuckWallace]

be curious to know if any of the previous posters (or the OP of this thread) have had their issue completely solved for extended time periods due to the amplifier swap.

I'm wondering this exact same thing. My 2024 had the no audio issue once within the first month of ownership (June 2023). It didn't happen again until a few months ago, but has been happening more frequently as of late. I'm also now having issues with the steering wheel skip/seek buttons not working until the truck is turned off/back on. I, too, think it's a software issue.

My truck is going to the dealer this week to have this looked at (as well as some other minor annoyances), but I'd really rather not have the interior torn apart to replace the amp if it's just going to keep happening.

 

[Renegade24]

I found this today:

I’ve been messing with mine this morning and turned quick startup off. Went to town and have started the truck 7 times so far and radio is working with no problems. If it stops working again I’m going to try a few of these other tricks

 

[Renegade24]

Absolutely do not want to take my truck to the dealer. I have a terrible horror story with a Ram diesel I had years ago and dealing with warranty issues lol

 

[echo_mtn]

I found this today:

I’ve been messing with mine this morning and turned quick startup off. Went to town and have started the truck 7 times so far and radio is working with no problems. If it stops working again I’m going to try a few of these other tricks

Sad to report that the Quick Startup thing has not solved it for me. It went about 2.5 weeks without audio going out, and then it happened again.

 

[echo_mtn]

My truck is going to the dealer this week to have this looked at (as well as some other minor annoyances), but I'd really rather not have the interior torn apart to replace the amp if it's just going to keep happening.

My thoughts exactly. Even if it worked, it might be trading one problem for another (rattles after reassembling all the dash components, etc.)

 

[echo_mtn]

I found this today:

I’ve been messing with mine this morning and turned quick startup off. Went to town and have started the truck 7 times so far and radio is working with no problems. If it stops working again I’m going to try a few of these other tricks

Yeah the trick in the video is how I force it to come back, but it's a temporary solution.

I thought about doing a hard reset (i.e. disconnecting the battery and reconnecting after a short wait), as that's a recommended fix in the PIT6406A bulletin about the issue, but I've seen enough posts in other forums from people who have tried this to convince me that it's not even worth it - it still happened for them afterwards.

Ultimately, GMC just needs to get their act together and fix it. It's such a widespread problem across a number of model years; the fact that it has gone unsolved as long as it has is unacceptable. I've thought about contacting GMC and trying to get in touch with their software engineering department to offer up my vehicle for remote diagnostics, since it has the "no audio" issue pretty regularly. They'd probably ignore me or tell me to pound sand, but might be worth a try.

 

[Ballaz]

Has anyone dealing with the no sound issue, changed out the sound system (amp included) and still experiencing the same thing? The Bose is lackluster and I am wondering if I can solve 2 problems at once.

 

[echo_mtn]

A hack that you guys might want to try...

I've been turning on the turn signal first thing to force the audio on when starting the truck, and (knock on wood) I haven't had loss of audio in a little over a month, which is the longest stretch I've had without the problem.

I have a suspicion that this all stems from some kind of a "sequencing" thing during startup - not sure if anyone's noticed it, but GM seems to have put a little startup audio "click" into the boot sequence for the infotainment system. I'm guessing they are using this as a trace for their own debugging purposes.

Anyways... yes, it's a dumb hack, and no, we shouldn't be having to use this janky maneuver on our $70k+ trucks just to make sure we have audio, but give it a try and let us know if it helps...