Idol 4S SD card dismount issues?

Maps and Apps on the phone. "Disposable" media on the card.

For W10M I shoot pics and vidz to internal as it seems to process better/faster. Then I occasionally move them off and triage them on PC. Only put the "keepers" back on and those go to SD since I have OneDrive image backup and original files I want on my laptop.
 
That's exactly what I do on any of the phones I've got with sd card (1520, 950xl, elite x3), only store pics, maps and WhatsApp backups in my case. However, it still shows the sd eject before disconnect warning, which that at some point the card disconnected itself anyways, so this doesn't fix the problem sadly
 
I'm mulling over the significance of the SD card to me personally, but the reality is that it's a feature that I fully intended to use that simply isn't working right. It's like finding out you can't reliably use the back row seating of your brand new minivan because they're prone to stowing away on their own and getting stuck. It's unacceptable.

And right now, it's just an inconvenience. But there's invariably going to be data loss or corruption of the SD card itself when the dismount happens at the wrong time and that's what I can't be dealing with.
 
I'm mulling over the significance of the SD card to me personally, but the reality is that it's a feature that I fully intended to use that simply isn't working right. It's like finding out you can't reliably use the back row seating of your brand new minivan because they're prone to stowing away on their own and getting stuck. It's unacceptable.

And right now, it's just an inconvenience. But there's invariably going to be data loss or corruption of the SD card itself when the dismount happens at the wrong time and that's what I can't be dealing with.

Is it just your device? I only saw one other person (in this thread at least) post about the same issue...what could be different that you are doing or not doing I wonder. For two in a row to do that and two separate SD cards???
 
Is it just your device? I only saw one other person (in this thread at least) post about the same issue...what could be different that you are doing or not doing I wonder. For two in a row to do that and two separate SD cards???

Beats me. I've tried to isolate the problem since I got the replacement model yesterday. I've only got one app on the SD card for now, which is not being actively used. Tried it with bluetooth on and off. Encryption is currently off. Windows Hello is currently off.

Problem seems to occur whether phone is in use or not. Happened again this morning around 8am while phone was on my bedside table unused. Phone was unused when it happened last night also. Phone isn't warm when I check it, so it doesn't appear to be related to heat expansion that might cause the card to shift slightly. Feels like a software issue more than anything else, but it might involve multiple factors.

And it's definately a fairly common issue. Folks in this thread are seeing it, on reddit, etc. Not just this phone either mind you, so not sure if W10 is just uber sensitive about the state of installed SD cards and ejects them the second there's a blip of any kind rather than pausing I/O for a sec and rechecking the status of the card periodically.
 
Beats me. I've tried to isolate the problem since I got the replacement model yesterday. I've only got one app on the SD card for now, which is not being actively used. Tried it with bluetooth on and off. Encryption is currently off. Windows Hello is currently off.

Problem seems to occur whether phone is in use or not. Happened again this morning around 8am while phone was on my bedside table unused. Phone was unused when it happened last night also. Phone isn't warm when I check it, so it doesn't appear to be related to heat expansion that might cause the card to shift slightly. Feels like a software issue more than anything else, but it might involve multiple factors.

And it's definately a fairly common issue. Folks in this thread are seeing it, on reddit, etc. Not just this phone either mind you, so not sure if W10 is just uber sensitive about the state of installed SD cards and ejects them the second there's a blip of any kind rather than pausing I/O for a sec and rechecking the status of the card periodically.
Try putting zero apps there next time you reset the phone toggle that option to device instead of SD card. Have you done that yet?

I have never seen this on my newer devices (x3, 950, 950xl) but I have a habit of not letting apps install there. Only photos/media/downloads etc. The IDOL 4s I have not decided to put the sd card in yet.
 
Try putting zero apps there next time you reset the phone toggle that option to device instead of SD card. Have you done that yet?

Yeah, I did this earlier. I've also installed a slightly slower 64GB Sandisk card that I had in my tablet. The other two cards were hi-performance dealies with high read/write speeds, so we'll see if that makes a difference.

EDIT: Aaaaaand......Another dismount, with no apps/media being read or written to the card. That's four in about 24 hours.
 
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The SD bus is rated up to 256GB, that tells me it is at least UHS-I rated. The SoC is likewise capable as is the OS.

Using SD Card R/W Test app on my Idol 4S and a Samsung EVO 32GB UHS-I card I get the following with a 64MB test file on continuous write/read:
Write - (last 10 entries)
11.62 MB/s
13.49 MB/s
15.83 MB/s
16.83 MB/s
19.46 MB/s
13.67 MB/s
13.73 MB/s
13.29 MB/s
15.67 MB/s
14.49 MB/s

Read - (last 10 entries)
192.45 MB/s
191.68 MB/s
192.06 MB/s
187.30 MB/s
187.28 MB/s
181.66 MB/s
190.07 MB/s
179.57 MB/s
187.34 MB/s
186.16 MB/s

It is vastly faster at read than a same card of this exact description when tested in my laptop SD slot. Write times are similar.

UHS-III cards are backward compatible with all previous classes. The only caveat is that SD and SDHC slots will not read exFAT formatted cards.
 
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The SD bus is rated up to 256GB, that tells me it is at least UHS-I rated. The SoC is likewise capable as is the OS.

Using SD Card R/W Test app on my Idol 4S and a Samsung EVO 32GB UHS-I card I get the following with a 64MB test file on continuous write/read:
Write - (last 10 entries)
11.62 MB/s
13.49 MB/s
15.83 MB/s
16.83 MB/s
19.46 MB/s
13.67 MB/s
13.73 MB/s
13.29 MB/s
15.67 MB/s
14.49 MB/s

Read - (last 10 entries)
192.45 MB/s
191.68 MB/s
192.06 MB/s
187.30 MB/s
187.28 MB/s
181.66 MB/s
190.07 MB/s
179.57 MB/s
187.34 MB/s
186.16 MB/s

It is vastly faster at read than a same card of this exact description when tested in my laptop SD slot. Write times are similar.

UHS-III cards are backward compatible with all previous classes. The only caveat is that SD and SDHC will not read exFAT formatted cards.

How much slower is the write read from the SD card as compared to internal storage, are you able to test?
 
I've now put an ancient Toshiba 4GB MicroSD card I had into the phone. I'm assuming it's formatted with FAT32, so we'll see if that makes a difference.
 
How much slower is the write read from the SD card as compared to internal storage, are you able to test?

Not really... I could test it via laptop as an external drive, but then we are really looking at the USB speed. I've not seen a program to test the R/W of internal storage on Windows Phone, but then again, I've not looked. Maybe Lumia Phone Test Application would do it? I have it on my laptop, but I've never used it. It takes a long time to run apparently.
 
I've now put an ancient Toshiba 4GB MicroSD card I had into the phone. I'm assuming it's formatted with FAT32, so we'll see if that makes a difference.

Been a day plus with the Toshiba 4GB card installed and no dismount. No idea at this point whether the phone has a beef with exFAT formatted cards or something else is going on.
 
This phone has 64 gigs of internal storage. Are we so used to having phones with abysmal storage that we've conditioned ourselves to "needing" SD cards? Nexus, Pixel and iPhones have never had external storage and they outsell Windows by a trillion so..... Yes they offer 128 models but they don't sell nearly as many as 32 and 64.
 
This phone has 64 gigs of internal storage. Are we so used to having phones with abysmal storage that we've conditioned ourselves to "needing" SD cards? Nexus, Pixel and iPhones have never had external storage and they outsell Windows by a trillion so..... Yes they offer 128 models but they don't sell nearly as many as 32 and 64.
Removable storage is more desirable than built-in (when it is working) for anything that doesn't require internal storage speed to use. If this thing didn't use a tray for the SD, I would have put the thousands of songs, hundreds of wallpapers, documents, and some HD movies on the SD card instead of the internal storage. It takes hours to move that much between a PC and a phone's internal storage, but maybe 1/5 that amount of time to and from an SD card. If the SD card doesn't work or causes problems because of the card or the phone, that's a different story. Or as in my case, if you detest trays and the phone in question uses a tray for the SD card.
 
Removable storage is more desirable than built-in (when it is working) for anything that doesn't require internal storage speed to use. If this thing didn't use a tray for the SD, I would have put the thousands of songs, hundreds of wallpapers, documents, and some HD movies on the SD card instead of the internal storage. It takes hours to move that much between a PC and a phone's internal storage, but maybe 1/5 that amount of time to and from an SD card. If the SD card doesn't work or causes problems because of the card or the phone, that's a different story. Or as in my case, if you detest trays and the phone in question uses a tray for the SD card.

When you got USB C at USB 2.0 speed yes it does. Have you used a USB C phone on a USB 3.0 port yet that fully supports it? Or OTG? Then now we are talking...Can't wait for a W10 phone to come out with that kinda speed.
 
When you got USB C at USB 2.0 speed yes it does. Have you used a USB C phone on a USB 3.0 port yet that fully supports it? Or OTG? Then now we are talking...Can't wait for a W10 phone to come out with that kinda speed.
With my 950XL, I just moved my SD card from the 1520 it replaced. I transferred files to the Idol using a USB3 port on the PC and it was SLOW as in hours.

BUT, plugging a phone that only has USB2 to transfer files to or from a PC is massively slower than USB2 speeds with every phone I've ever had. So I don't think USB3 helps much. If I ever think its worth the time, I'll try some large transfers with the 950XL to confirm.

I suspect the reason for the slowness is that Windows on the phone is doing a whole lot more than just passing data thru. It's doing all the file system overhead that was much faster when an I5 or I7 on the PC was doing it. Plus I've watched the phone create thumbnails for files as they came across and likely doing a bunch of other stuff in real time. But if you plug in an SD card some of those things had already been done by the PC that wrote the card and the rest gets done in the background on the phone after the card is plugged in.
 
With my 950XL, I just moved my SD card from the 1520 it replaced. I transferred files to the Idol using a USB3 port on the PC and it was SLOW as in hours.

BUT, plugging a phone that only has USB2 to transfer files to or from a PC is massively slower than USB2 speeds with every phone I've ever had. So I don't think USB3 helps much. If I ever think its worth the time, I'll try some large transfers with the 950XL to confirm.

I suspect the reason for the slowness is that Windows on the phone is doing a whole lot more than just passing data thru. It's doing all the file system overhead that was much faster when an I5 or I7 on the PC was doing it. Plus I've watched the phone create thumbnails for files as they came across and likely doing a bunch of other stuff in real time. But if you plug in an SD card some of those things had already been done by the PC that wrote the card and the rest gets done in the background on the phone after the card is plugged in.

Ya anyway you look at it, it is USB bus type-like speed. Compared to SD Card/Onboard ROM which PCI type-like speed.
 
Also just because it is USB C does not necessarily mean it supports USB 3.0 speed.
 
I have this issue with SD card dismounting at least a few times a day religiously, especially when my phone is sitting on the magnet car mount. Ok so the other day I read somewhere someone placed a sticky note on the back of their SD card cut it to shape and then put it back in tray and reinserted it. Sounded logical, what the heck gave it a try on Friday and I have not had one dismount yet! :grin: "Knock on wood" but I so far so good all...just thought I would share...
 
Is the USB-C port in the 4S only USB 2.0?
What about the USB-C in the 950/XL? Always been curious.