Bluetooth Distortion
Thread Starter
Newbie
Joined: Jan 2018
Posts: 4
Likes: 0
2012 E350
Bluetooth Distortion
My 2012 E class recently began having a heavy distortion at the speaks of the Harman Kardon system. I know that it's a Bluetooth issue because it does not do this when I play a CD or AM/FM. Has anyone experienced this and successfully remedied? I guess specifically this problem exists when I play music via iTunes on my phone. Nothing out of the ordinary when I receive phone calls through the Bluetooth.
Senior Member
Joined: Nov 2018
Posts: 443
Likes: 69
From: California
2013 E550 4MATIC - P1, P2, SPORT
I had this issue when I got my E as well and it was infuriating. Then I found under the audio options (I think it was) for the Bluethooth something called "Boost". Disable it! Immediately. I bet that will resolve the issue.
(If you can't find it I'll go out to my car and figure out exactly where it is, but I'm pretty sure it's under Audio as I mentioned.)
(If you can't find it I'll go out to my car and figure out exactly where it is, but I'm pretty sure it's under Audio as I mentioned.)
Junior Member
Joined: Dec 2024
Posts: 19
Likes: 2
From: Johannesburg south Africa
2016 W166 gle 350d
Good day,
I recently got a 2016 gle with Harmon kardon sound system and I am also having the issue of it being distorted only with Bluetooth. CD works just fine.
Where did you find this feature or setting?
I recently got a 2016 gle with Harmon kardon sound system and I am also having the issue of it being distorted only with Bluetooth. CD works just fine.
Where did you find this feature or setting?
MBWorld Fanatic!
Joined: Jan 2016
Posts: 2,757
Likes: 889
From: In the Shadow of the Tetons
2013 ML350 Bluetec
In my experience, having the phone's output volume all the way up on a bluetooth connection results in distortion on the playback device, no matter the volume setting on the device (HK headset in this case). I've found that turning down the phone volume results in a much cleaner sound. Just a single notch below full works.
Senior Member
Joined: Mar 2018
Posts: 496
Likes: 154
From: KY
2015 E63S Sedan, 2014 E550 Coupe, 2013 E350 Wagon
Over the holiday I resolved my Bluetooth distortion by following my gf’s advice (she’s smarter than me)…I deleted and reinstalled Spotify on my phone (iPhone 15 Pro Max). That was it.
I truly thought I had outdated software in car, or faulty Bluetooth adapter or something…until her iPhone played clearly using her Spotify when connected via Bluetooth to my stereo. I had already verified CD played clearly. Just my $0.02. Perhaps a setting within my Spotify was off, however we did a stare and compare of settings before I did the delete and reinstall too
I truly thought I had outdated software in car, or faulty Bluetooth adapter or something…until her iPhone played clearly using her Spotify when connected via Bluetooth to my stereo. I had already verified CD played clearly. Just my $0.02. Perhaps a setting within my Spotify was off, however we did a stare and compare of settings before I did the delete and reinstall too
Newbie
Joined: Jul 2025
Posts: 4
Likes: 0
2011 w212 wagon
My newly acquired 2011 e350 also has the Bluetooth distortion issue. It's not app related because playing mp3s on the phone, YouTube, spotify etc... all play with distortion over Bluetooth. Doing a "system reset" then re-syncing the Bluetooth fixed the distortion for a couple of days, but it's come back. "Boost" is off, my volume is around 60% on the phone. Aux plays with perfect clarity so I'm using that for now.
Hands down, the worst part about doing the system reset is that the clock takes FOREVER to scroll to the right time. My car doesn't seem to have sat sync for the clock, and the way in which you set the minutes and hours is in Comand, scrolling slowly minute by minute until you reach the right time. There doesn't seem to be an adjustment for the hours, only minutes, so you're counting up through multiple hours to get where you need to be.
I've considered one of those 7" android upgrade units, I think those have their own Bluetooth hardware? In the meantime the built in Bluetooth is problematic.
Hands down, the worst part about doing the system reset is that the clock takes FOREVER to scroll to the right time. My car doesn't seem to have sat sync for the clock, and the way in which you set the minutes and hours is in Comand, scrolling slowly minute by minute until you reach the right time. There doesn't seem to be an adjustment for the hours, only minutes, so you're counting up through multiple hours to get where you need to be.
I've considered one of those 7" android upgrade units, I think those have their own Bluetooth hardware? In the meantime the built in Bluetooth is problematic.
