S9/ SD Card Problems

[Nord]

For S9 Users:

1. Are you still using your original SD card in your S9 ??? Do you use another SD card as well ???
2. If you use another card ??? Why did you switch ??? Has it had any effect on skewing ???
3. Have you looked closely for a "skewing" of data at all ???
4. Do you or have you had: "skewed data" ??? Has the skewing increased over time ???
5. How did you stop the skewing ???
6. Do you "lock" the SD card when in your PC ???
7. Do you "power down" your S9 ??? Do you leave your card in the S9 when you power down ???
8. How many sessions (24 hr days) are on your SD card now ???
9. How many days have you used your S9 ???
10. Do you ever "overwrite" your data or do you always "discard" when DL'ing data to ResScan.
11. When looking at the contact slots of your SD card... do you notice cuts to the plastic and extra pieces of blue plastic obstructing the slots ???
12. Do you leave the card in the S9 most of the time or just put the card in the S9 before using the machine ???
13. Have you re-formatted the SD card ??? Do you use the S9 or your PC for formatting ???

Hoping to get to the bottom of data/ SD/ software issues...

Thanks
Nord

[Arizona-Willie]

1. Are you still using your original SD card in your S9 ??? Do you use another SD card as well ???
Yes, still using original but thinking of buying another 'cause this one sometimes gives problems.

2. If you use another card ??? Why did you switch ??? Has it had any effect on skewing ???
Haven't switched.

3. Have you looked closely for a "skewing" of data at all ???
Yes, haven't had a skewing problem.

4. Do you or have you had: "skewed data" ??? Has the skewing increased over time ???
Again no skewing.

5. How did you stop the skewing ???
No skewing observed.

6. Do you "lock" the SD card when in your PC ???
Yes I do.

7. Do you "power down" your S9 ??? Do you leave your card in the S9 when you power down ???
Not sure what you mean by " power down " if you mean unplug it ... then no it stays plugged in.

8. How many sessions (24 hr days) are on your SD card now ???
I dunno.

9. How many days have you used your S9 ???
32? 33?

10. Do you ever "overwrite" your data or do you always "discard" when DL'ing data to ResScan.
I discard.

11. When looking at the contact slots of your SD card... do you notice cuts to the plastic and extra pieces of blue plastic obstructing the slots ???
OK now I gotta go pull the card .... nope ... contacts look good.

12. Do you leave the card in the S9 most of the time or just put the card in the S9 before using the machine ???
I leave it in the machine all the time. I take it out in the morning, download the data, review the data, then put the card back in the machine and fill the tank.

13. Have you re-formatted the SD card ??? Do you use the S9 or your PC for formatting ???
Yes, I have re-formatted and I've used both methods.

I've had a couple of occassions where Rescan wouldn't read the card. I could look at the card with explorer and the data files were there but I had trouble getting the card to read. I've put it back in the machine and then removed it again and once it worked then but most of the time I have to fiddle with it and put it in and out of the card reader and try and try. So far I've been able to get it to read and haven't lost any data. And yes I do copy the files to a folder on my hard drive for a backup.

I suspect this card isn't the highest quality available. Next time I'm in Staples I'm gonna see about a different one.

I just took another real close look at last nights data and several of the obstructive and central apneas were flagged just maybe a quarter of a second after the flow line began to rise again, but the last two the flag was planted perfectly right at the end and as the line began to rise.

I'm not sure if a quarter of a second constitutes " skew " but I don't think so. I've seen where some are seeing many seconds delay.
But since the purpose of the flag is just to show you that you had one about here, I'm not sure if a little skew constitutes a problem.

It is curious, though, that it planted the flags 1/4 second off until the last two which it planted exactly at the end of the apnea just as the flow line is going to goup. Ha, just looked at Monday nights chart and the flags are planted EARLY!! by a fraction of a sec.

I suspect this is just the programing for the flag display. It probably does quite a bit of math and simple rounding errors could introduce that kind of variation.

These programmers were the ones who graduated 198th in a class of 200. The software has quite a few things that should be much better / different.

[Nord]

Hi AWillie

Thanks for your response...

I agree with you on the quarter second delay or advance for event flags... has to be out by more than 1 or 2 seconds to be notable. I find the Obstructives and Centrals are fairly accurate buy Hypops are just in the general area... they may be 1 or 2 seconds out of place but its hard to tell.

Most people are getting a skew of more than 2 seconds when the Flow graph starts and when the Leak, FL, Pressure, MV starts or ends. Its causing a skew of breathing graph... sometimes it gets much worse and eventually 50 to 60 seconds of Flow goes missing. I have had an Apnea event standing alone after the machine had been shut off for 2 minutes

Ya... the ResMed SD disks are low quality... I have 2 and both show messed up contact slots. I have bought several new cards (Scandisk) and have just started using them so not much to report yet... no skewing.

Since you haven't had a problem since your original corruption... keep doing what you're doin'. I'm trying to find out why some are and some aren't.

Nord

[dave21]

1. Are you still using your original SD card in your S9 ??? Do you use another SD card as well ???
NO, using a 16gb SanDisk card

2. If you use another card ??? Why did you switch ??? Has it had any effect on skewing ???
Sandisk SDHC, very few skews.

3. Have you looked closely for a "skewing" of data at all ???
Yes

4. Do you or have you had: "skewed data" ??? Has the skewing increased over time ???
Yes

5. How did you stop the skewing ???
Format the SDHC card and power cycle the S9

6. Do you "lock" the SD card when in your PC ???
Yes and that doesn't stop the skew

7. Do you "power down" your S9 ??? Do you leave your card in the S9 when you power down ???
Yes to stop it skewing

8. How many sessions (24 hr days) are on your SD card now ???
One usually

9. How many days have you used your S9 ???
60 days

10. Do you ever "overwrite" your data or do you always "discard" when DL'ing data to ResScan.
Discard

11. When looking at the contact slots of your SD card... do you notice cuts to the plastic and extra pieces of blue plastic obstructing the slots ???
No

12. Do you leave the card in the S9 most of the time or just put the card in the S9 before using the machine ???
Yes

13. Have you re-formatted the SD card ??? Do you use the S9 or your PC for formatting ???
Yes using PC, Fat32

[Nord]

I'm guessing... no more problems... that's good.


Nord

[dave21]

I haven't hit into the problems again but I have been power cycling the machine most nights (not every night).

I'm now going to start to not power cycle the machine and see if it starts coming back for a week. Then if I don't see a skew similar to what I've seen in the past I'm then going to write enable the SD card when in the Laptop.

Thanks
Dave

[KatieW]

1. Are you still using your original SD card in your S9 ??? Yes.
Do you use another SD card as well ??? No.
2. If you use another card ??? Why did you switch ??? Has it had any effect on skewing ???
3. Have you looked closely for a "skewing" of data at all ??? Yes, seen at 5 minute level.
4. Do you or have you had: "skewed data" ??? Yes
Has the skewing increased over time ??? don't know
5. How did you stop the skewing ??? Formatted card April 4, and have been powering down the S9 daily, the 1st day, I used on/off button, but now unplug at back of S9, after learning to do that.
6. Do you "lock" the SD card when in your PC ??? yes
7. Do you "power down" your S9 ??? Yes. Do you leave your card in the S9 when you power down ??? Yes.
8. How many sessions (24 hr days) are on your SD card now ??? 3
9. How many days have you used your S9 ??? 21
10. Do you ever "overwrite" your data or do you always "discard" when DL'ing data to ResScan. Discard
11. When looking at the contact slots of your SD card... do you notice cuts to the plastic and extra pieces of blue plastic obstructing the slots ??? No
12. Do you leave the card in the S9 most of the time or just put the card in the S9 before using the machine ??? Leave it in most of the time.
13. Have you re-formatted the SD card ??? Yes, on April 4. Do you use the S9 or your PC for formatting ??? PC

I formatted my card on April 4. I downloaded the data on April 5, at 7 pm, and there was no skewing. Today, I will DL the data for April 6-8, and see what I get.

Thanks for your work on this, Nord.