USB music auto-resume related to allocation unit size

[ianc]

Hi folks,

Am loving the car, but my chief hate on it thus far has been the difficulty in getting my MP3\FLAC library to play and auto-resume after the car goes into deep sleep, ie. the next morning when I get in to commute to work. I've seen a lot of posts about this with no real solution.

When I took delivery, I experimented with a dinky 2 GB USB drive which was all I had laying around, and it worked flawlessly. It always resumed playing right where I left off without exception, so based on the strength of that, I ordered a 256 GB drive so I could put my complete library on it. That, unfortunately, did not work. When getting in the car in the morning, the drive didn't have to be rescanned, but I would have to enlarge the mini-player, select USB as a source, and select a tune to start it. Annoying...

I decided to work up, so selected a 16 GB drive and filled it with music. That worked fine. Next, I took a 32 GB drive and copied the exact same files from the 16 GB drive to it. That did NOT ever work, so my next thought was to check the allocation unit size.

I've been using guiformat on Windows to format the drives as FAT32. When formatting a 16 GB drive with this tool, the default allocation unit size is 8K, but for 32 GB, it's 16K, which I had just accepted although it is user-selectable. I decided to reformat the 32 GB drive using an 8K allocation unit size, then copied the same files back to it from the 16 GB drive.

Tested it this AM, and lo and behold, it auto-resumed right where it left off last nite.

Looking good so far, and will be testing a 64 GB drive next. Not sure what the practical limit on drive size is with an 8K sector size though. Anyway, hope this helps someone...

Ian

 

[sduck]

That's interesting. I have no idea what the allocation sizes are with my ssd - formatted with a mac using disk utility, using the Paragon Software ExtFS extension, using ext4. But it resumes properly over power cycles.

I do still experience occasional glitches where it doesn't remember - maybe one out of every 20 times. What fixes it is to put the car back in park, get out, close the door, then get back in. Your last spot will be back.

 

[ianc]

Well, I'm sad to say that I may have partially jumped the gun on this. Subsequent behavior has been more like sduck reports. I still get odd random failures to mount, so it's not a cure-all. However, it's a significant improvement in that before with anything above an 8K AU, it was guaranteed to fail; I never had a single success having music auto-resume. Using an 8K Au at least allows it to work the majority of the time for me, and the method of closing the door and opening it again does seem to work also. I also had luck formatting a 256 GB drive with guiformat using an 8K AU.

Now if Tesla could just fix things so that they work as well as the $5 Android app I'm using on my phone...

Ian

 

[GraemeI]

Hi, I have re formatted my 32 GB USB drive to an allocation size of 8K, but still no auto resume.
I have a Model S 75D with SW version 2020.4.1.
What I have found out that does work every time if a little annoying is to open the door for about 10 sec. Close the door wait until the display goes out then reopen door. The music resumes on the USB exactly where it was.

 

[sduck]

I've been doing some more messing with this, trying to find why some things work, and some things don't. I've already determined that using a partitioned drive doesn't work reliably. And running the drive through a hub can be problematic. And that pretty much anything that's not an ssd doesn't work. So, I had (note the past tense, more on that later) 2 ssd drives - one is my over a year old sandisk extreme, and a newer one by caldigit. The caldigit is supposed to be super fast, but actually tested a bit slower than the sandisk. So, for quite a while i was using the sandisk for music (formatted ext4 - my music disk is always that way), and the caldigit for sentry/dashcam. This combo worked well, the music almost always resumed correctly. Once in a rare while I'd have to get out, close the door, get back in to get it to resume properly. Then, my car was in the shop for a month getting a fender bender fixed, and I had to mess with things, so switched the drives around. Then, the music stopped auto resuming like it used to - I was almost always having to do the get out of the car dance to get things working. Annoying. And, someone here had suggested getting a M.2 drive, but only if you could find a really fast one, so I did some comparison shopping, and ended up with a Crucial MX500 https://www.amazon.com/gp/product/B077SL4FZG/ and a fairly inexpensive case - https://www.amazon.com/gp/product/B0788HBLDZ/ - total cost about the same as a comparable normal ssd. And tested it - it's about the same speed as the sandisk according to the blackmagic tester. But, I did the ext4 format, and put my music stuff on it, and it's been working flawlessly - has resumed playback perfectly every time so far! It's only been 4 or 5 days, so it's not conclusive yet, but I'm thrilled to have it working at least this good!

 

[Kevy Baby]

My thoughts on the getting-out-of-the-car trick. Either

1. There is something else that is triggering the "correction" that hasn't been discovered yet, or
2. This is some really screwed up programming

Actually, #2 prevails regardless. Daaaaaamn

 

[sduck]

My vote is #2. I think they basically "borrowed" some freeby software from 2001 or so, and crammed it into the car, making whatever small changes needed to get it working. It's so basic it could hardly be anything else. Not to mention about 2 years ago, when I first started communicating with tesla about the usb system problems - back when they would actually respond and send you to the right people, they basically corroborated this, and said that a whole new system was planned, and would be introduced with V9 or soon afterwards. But that never happened.

 

[ianc]

The majority of what I've got on my USB drive at present is 256 KB\s or greater MP3's. I've been reading a bit and from what I can determine, bluetooth can (barely) handle 320K, but the 500-800K of FLAC's would be right out. I'm wondering if a detectable audible difference actually exists if you're using high bit-rate MP3's (USB vs. Bluetooth) as opposed to FLAC's?

It would be so much more convenient to just start the MP3 player on my phone and have one device\playlist I can listen to at home, work and in the car rather than screw endlessly with the stupid car. Will have to do some testing to see. At nearly 60, my ears are not the sharpest tacks in the box...

One thing I've really enjoyed in the car however is the ability to display embedded album art in the mini player, which my last car didn't do. Not sure if this will work streaming bluetooth MP3's from my phone as I've only got folder.jpg's on it right now, no embedded album art.

Will have to do some testing...

ianc

 

[thecloud]

My observations over the past few years:

1. MP3 tracks will auto-resume in my Tesla, but FLAC tracks will not.

2. Best quality for MP3 is obtained with 320 kbps CBR (constant bit rate) encoding.

3. FLAC is preferable to MP3 since it's a lossless format and its sound quality is superior (when encoded at a 16 bit sampling rate; too high a bit rate will overwhelm the processor.)

If you absolutely need playback to auto-resume (e.g. you're listening to an audiobook), then you probably want to use MP3. If you're listening to music and care about the audio quality, use FLAC.

 

[thecloud]

My observation over the past 5 years: MP3 tracks will auto-resume, FLAC tracks will not.

 

[sduck]

See my post (#5) above - I use almost all flac files, they auto-resume fine.

 

[thecloud]

See my post (#5) above - I use almost all flac files, they auto-resume fine.

Interesting. So auto-resume might correlate with drive access speed? My experience has been with a variety of USB3 thumb drives, but not with a SSD drive, so sounds like I should give that a try. (Not sure how my edited post got split into two posts above... didn't intend to do that.)