S9 flow skew bug... Anyone else seeing this?

I'm still getting skew that seems to double daily.
I wiped the card and put it back into the S9 on the 3rd.
FIrst night - 1 second skew as predicted.
Last night - 2 second skew.

This is the versioning stuff I see for ResScan:
ResScan Version 03.10.006
Launcher Version 0.2.0.59
Clinical Version 0.7.0.259
(Help --> About)

This is the versioning stuff I see for the S9:
SW SX474-0601
(Press 'i', dial 2 clicks clockwise to find this.)

I wonder if something is messed with my machine...
Do others see these version numbers or are yours different?

DreamDiver, I see the identical numbers as you, for ResScan and S9.

Exact same versions for me but no skew. So far, shutting it down (every day) by pressing the power button for 3 seconds seems to be stopping the skew for me at least. (Or something else we haven't figured out yet.)

-Corey

Thanks KatieW, coreyg,

You know, it's just not worth worrying about. Maybe I have a bum SD card.
Are either of you taking a nap during the day?

DreamDiver wrote:Thanks KatieW, coreyg,

You know, it's just not worth worrying about. Maybe I have a bum SD card.
Are either of you taking a nap during the day?

No, but I do turn off the cpap during the night, if I go to the bathroom, adjust mask, etc.

Sounds like y'all need to ID who is doing what practice to narrow what might eliminate the problem. Say, name the practices Dave 21, FF, DD, BillB, BigK, Katie & each will document what they are doing with the card & the skewing they are getting as well as IDing their version of the software. There's got to be a commonality of practice(s) that causes the skew. Disconnecting power in between sleep sessions vs 3-sec power off before bed. Locking card. Leaving card in device overnight. No overwriting data. All may or may not be part of the solution.

Too, it seems as if there are several types of skewing going on, tho that might be muddle-headed reading . That should also be ID'd and then investigated to see if it's associated with specific practices.

And then, there's that 1-hr gap issue that still seems to be hanging around: related to time changes, naps, what?

There will emerge from these exercises a best practices for getting un-skewed data even if frustrating & time-consuming to get there -- this is where a ResMed engineer or 2 would be really helpful to ID each issue & come up with best practices for users. But, each time a company rep has shown up, they get flammed from unhappy users and leave...ah well, such is life.

no naps and I download the data once a day.

-Corey

DreamDiver wrote:Thanks KatieW, coreyg,

You know, it's just not worth worrying about. Maybe I have a bum SD card.
Are either of you taking a nap during the day?

Hi DD... some questions for you...

I'm watching your skew details with interest.

You wiped and formatted the card and shut the S9 down but still getting the skew ???
You were going to change cards and try again... did you ???
What is the status of your skewing now ???
Are you still taking the card out of the S9 more than once per session ???
Are you unplugging the machine at least once per day for at least 1 minute ??? At what time ???
Does the clock time on your computer match your clock time on the S9 ???
At what time do you remove the card and view your data ???

Nord

Out of Interest for the group....

Just got back from a trip where I took the S9:

Began the trip... the S9 had no skews other than the basic 1 and 2 seconds for 2 days prior.

The SD card was full of data from previous days that was not skewed;
Left the SD card in the S9 for the entire time;
Powered down by unplugging the machine each day for at least 1 hour;
I had naps and sleep sessions during each day where the machine was turned on and off multiple times;

When I DL'ed the data to ResScan... I had skewed flow that got worse and missing flow times as follows:
First Session: ranges between 4 and 8 seconds early
Second Session: 9 seconds early and 53 seconds of Flow missing
Third Session: 10 seconds early
Forth Session: 11 seconds early and 51 seconds of Flow missing

I am just about to DL last night's data and find out where the skew is...

Nord

DreamDiver, I have another question for you. I had asked you and the others earlier in this thread how many days of detailed data you are downloading each time.

This was your response:

DreamDiver wrote:I have it set to quick start - not that quick start is all that quick. It usually takes a minute before it recognizes the SD card. It asks me if I want to overwrite or discard duplicate data. Since the data isn't really duplicate, I discard it.

I'm not sure that really answered my question. As your data is actually downloading I believe there is a progress bar. How many sessions of Detailed Data does it say it is downloading there? Dave21 said he only downloads one session each time. I'm just wondering if you and the others do too.

I've been trying to think of what people may be doing different. I believe that both DreamDiver and Dave21 are downloading the data before noon each day, and each discard duplicate data -- correct? If someone could come up with a list of all the possible variables, some of which Muse-Inc mentioned, and have each person explain how they conduct each step perhaps it'll be easier to determine the cause of the data skewing. I don't have an S9 machine to test, so I can't participate at this time, but here are some variables that I've thought of. Perhaps there are more pertinent questions that can be added.

• Do you lock the data card before reading on the computer?

• When do you insert the card into the S9 machine?

• Do you power down the machine? If so, HOW (unplug it or push button?, how long is power off?) and WHEN (what time of day)?

• What card reader are you using?

• Are you using a ResMed data card or other?

• Do you use the Eject or Safely Remove Hardware feature of Windows before removing the data card from the card reader?

• Exactly how are you downloading the data -- Do you download daily? What time of day (before or after noon)? How many Detailed sessions do you download each time? Do you Discard or Overwrite when prompted after download?

Nord wrote:When I DL'ed the data to ResScan... I had skewed flow that got worse and missing flow times as follows:
First Session: ranges between 4 and 8 seconds early
Second Session: 9 seconds early and 53 seconds of Flow missing
Third Session: 10 seconds early
Forth Session: 11 seconds early and 51 seconds of Flow missing

Great Nord, this is a good test and good results. I was thinking the other day because of DreamDiver and Katie'W's skews that they both have been having multiple sessions on the S9. I haven't yet been able to reproduce this myself with multiple sessions but it could be that these aren't matching up at the end/begginning of each multi-session and that might be impacting the skew or missing data more.

That said, when I've had skewing or missing data (which is the worst) I have always had single sessions on the S9

DreamOn wrote:DreamDiver, I have another question for you. I had asked you and the others earlier in this thread how many days of detailed data you are downloading each time.

This was your response:

DreamDiver wrote:I'm not sure that really answered my question. As your data is actually downloading I believe there is a progress bar. How many sessions of Detailed Data does it say it is downloading there? Dave21 said he only downloads one session each time. I'm just wondering if you and the others do too.

I can certainly see the machine getting confused if it's writing multiple sessions to the SD card, but I don't believe it's ResScan at fault here. I think it's the S9 that's getting confused. Although it would be a good test if someone has multiple sessions to only download one session at a time and see if that works, then don't save and then download all sessions from that day and see if there's any skew.

Thanks
Dave

I have 3 nights data on my current card and just push the left knob to turn off the machine (no power reset). No skews at all, but encountered one gap for an hour in the detailed data.

The prior card had 8 days of data with no skew nor gap.

dave21 wrote:I can certainly see the machine getting confused if it's writing multiple sessions to the SD card, but I don't believe it's ResScan at fault here. I think it's the S9 that's getting confused. Although it would be a good test if someone has multiple sessions to only download one session at a time and see if that works, then don't save and then download all sessions from that day and see if there's any skew.

Dave, this is a good idea. Just to clarify, by a "session" I meant one 24-hour period from 12:00 noon one day until 12:00 noon the next day. I believe this is how ResScan defines a session when it reports how many detailed sessions are being downloaded. This session may include both daytime naps (if any) and nighttime sleep. I was curious if everyone is only downloading one detailed data session each time. You're probably right that it's not the source of the problem, but I think every variable is worth looking at.

I've managed to get a skew last night (albeit minor one) at the end of the AHI graph. Check out the information in this post - viewtopic/p469458/viewtopic.php?f=1&t=5 ... 29#p469629

gpk111 wrote:I have 3 nights data on my current card and just push the left knob to turn off the machine (no power reset). No skews at all, but encountered one gap for an hour in the detailed data.

The prior card had 8 days of data with no skew nor gap.

Hi gpk...

I see you had no skew prior and changed cards after 8 days. Then used a different card which has 3 nights and now missing data...
I have some Questions:

1. Is the missing data exactly 1 hour and at what time?
2. Is it Flow data that is missing or is it some other data that's missing?
3. Is it still missing?
4. When you change the graph time in ResScan from 10 hours or 12 or 24 hours to 1 hour/1minute/30 seconds... does the missing data return?
5. Why did you change cards? What type/make of SD card are you using? Did you format with PC or S9?
6. How many days have you been running the S9?
7. Have you looked very, very, closely for any skews in any data prior to this?
8. Has there been any skews at all in the past ownership of S9?
9. Do you power down by unplugging cord?
10.Do you power up the machine more than once during any session (24 hrs)?
11.Do you DL data more than once a day to your PC?
12.What time do you remove card from S9?
13.What time do you DL data to your PC?

I am in the midst of several ideas about skewing... still testing theories...

Nord