You are here

MP3s: why do some play in my car and some not?

All about the tools and techniques involved in capturing sound, in the studio or on location.

MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Sat Aug 15, 2020 4:19 pm

My new Skoda has a USB socket through which to play music from a flash drive. So I copied a whole load of songs onto a USB drive from my Mac, mostly mp4 but quite a few mp3. But most of the mp3s won't play, the system says file type not supported. Some play however and by a bit of detective work it seems that the ones that play are ones where the cover art has copied over to the USB drive. Does this mean that these MP3s are different to the ones that the cover art hasn't copied over or is this just coincidence. All MP4s seem to play absolutely fine. I'm perplexed!
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby Hugh Robjohns » Sat Aug 15, 2020 4:43 pm

I'd be surprised if the cover art was the problem. The ones with the cover art are probably mp3s of 16/44.1 standard source audio.

So perhaps there's an issue with the other files having different sample rates (96k?) or word lengths (24bit?). Or maybe recorded in a VBR mode instead of CBR... Or even located in a sub-directories that make then unreachable to the player.

I'm sure a little detective work on the file properties will identify the differences between playable and unplayable files.
User avatar
Hugh Robjohns
Moderator
Posts: 28326
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: MP3s: why do some play in my car and some not?

Postby Folderol » Sat Aug 15, 2020 5:01 pm

VBR is my first suspect actually - a surprising number of players can't handle them :(

MY Skoda also has a USB port but I've never bothered to try it - I'm too used to just plugging my ancient iRiver H320 in to the 3.5mm jack socket :tongue:
User avatar
Folderol
Jedi Poster
Posts: 11354
Joined: Sat Nov 15, 2008 1:00 am
Location: The Mudway Towns, UK
Yes. I am that Linux nut.
Onwards and... err... sideways!

Re: MP3s: why do some play in my car and some not?

Postby The Elf » Sat Aug 15, 2020 5:25 pm

Yep, I've also had cars that refused to play VBR. These days I just stream everything from home on my phone and play that through the car stereo - all problems solved.
User avatar
The Elf
Jedi Poster
Posts: 14880
Joined: Tue Aug 14, 2001 12:00 am
Location: Sheffield, UK
An Eagle for an Emperor, A Kestrel for a Knave.

Re: MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Sat Aug 15, 2020 5:36 pm

I'm still doing my detective work, nothing obvious jumps out, different bit rates doesn't seem to be the issue and they're all 44.1 sample rate. How do you find out if they're CBR or VBR, this info doesn't seem to appear in the iTunes info? But it seems really odd that the ones where the art has copied to the USB drive seem to be the ones that play. Why wouldn't all the artwork copy over from iTunes???
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Sat Aug 15, 2020 5:59 pm

Found out about VBR v CBR and the vast majority of the files that won't play are regular CBR it seems, all 128, 256, 320 etc.
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby Folderol » Sat Aug 15, 2020 6:23 pm

Dr Huge Longjohns wrote:Found out about VBR v CBR and the vast majority of the files that won't play are regular CBR it seems, all 128, 256, 320 etc.
Well that's a first :shocked:
User avatar
Folderol
Jedi Poster
Posts: 11354
Joined: Sat Nov 15, 2008 1:00 am
Location: The Mudway Towns, UK
Yes. I am that Linux nut.
Onwards and... err... sideways!

Re: MP3s: why do some play in my car and some not?

Postby FrankF » Sat Aug 15, 2020 7:16 pm

The Elf wrote:Yep, I've also had cars that refused to play VBR.

I think you'll find that Philip K. Dick predicted that many years ago.
FrankF
Regular
Posts: 108
Joined: Fri Sep 13, 2002 12:00 am
Location: La Vendée, France

Re: MP3s: why do some play in my car and some not?

Postby Martin Walker » Sat Aug 15, 2020 8:12 pm

FrankF wrote:
The Elf wrote:Yep, I've also had cars that refused to play VBR.

I think you'll find that Philip K. Dick predicted that many years ago.

As he did many other things ;)


Martin
User avatar
Martin Walker
Moderator
Posts: 16239
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK

Re: MP3s: why do some play in my car and some not?

Postby Stratman57 » Sat Aug 15, 2020 8:54 pm

I to have a Skoda (4x4 Yeti), and I found that when I tried to play MP3s from an SD card, there was a limit to the number of subdirectories it could access. One I got rid of these it would play all of the files.

Regards, Simon.
Stratman57
Regular
Posts: 269
Joined: Wed Apr 20, 2005 12:00 am

Re: MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Sun Aug 16, 2020 11:10 am

Nope, good thought but it's not that either, the files that play and won't play are in the same top level folder.
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Sun Aug 16, 2020 7:33 pm

On a related note, anybody tried the bluetooth transmitters that plug into your iPod?
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby CS70 » Mon Aug 17, 2020 9:33 am

Can be a number of things - most likely a property of your car stereo, rather then the files.
Some have a max file limit - they can't play any files beyond the say 1024th, which will appear as random "unplayable" when the songs are ordered in anything else than the order they were phisically copied. Some support only FAT32. Some can't cope with ID3 tags (or ID3v2 or v3 etc) and get confused. Some have problems with different encoding paddings. Files with DRM protection. The player firmware creating a cache file on the disk listing files that are there (and then failing to update it). The list goes on (and for long!).

The fact you mention album art suggests an issue with ID3 tags - which is fairly common on hardware players. Try and take a song which doesn't play, strip all the ID3 tags and see if it does. Change the USB stick label. Look for hidden files in the USB stick you have.Take note of a file that doesnt play, put it on a new USB stick and try with that - if it works, it's likely caching issues.

Short of getting the logs directly from the hardware unit, it's difficult to say what of the myriad issues can be, so the only procedure is to try a lot of stuff until you hit what's what.
User avatar
CS70
Jedi Poster
Posts: 6068
Joined: Mon Nov 26, 2012 1:00 am
Location: Oslo, Norway
Silver Spoon - Check out our latest video and the FB page

Re: MP3s: why do some play in my car and some not?

Postby Dr Huge Longjohns » Mon Aug 17, 2020 10:07 am

That's all really helpful, thanks CS70! :thumbup:
User avatar
Dr Huge Longjohns
Frequent Poster (Level2)
Posts: 3719
Joined: Thu Apr 10, 2003 12:00 am
Location: Gallifrey
"The performance is 99.9% of what people hear"- J. Leckie
"It's all complete nonsense, anyone who knows what they're doing can deliver great results with whatever comes to hand" - H. Robjohns

Re: MP3s: why do some play in my car and some not?

Postby Hugh Robjohns » Mon Aug 17, 2020 10:33 am

Actually... good point about DRM protection. Are some of your files protected downloads?
User avatar
Hugh Robjohns
Moderator
Posts: 28326
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Next