I´m having troubles with the Devices Type Report, when I display the data from a certain month in the Devices Type Report the sum of every device is different from the total that appears down, I´m including a screen capture to try to explain myself better, this is not the first time that this happens it also happens on the Referrer Type report; there´s an explanation to this? Or am I doing something wrong?
The sum of all the line items is 68716 and is 31 more than the de-duplicated total. The difference 31 corresponds to rare scenario where a Unique Visitor was considered to have come through multiple Device Types.
Now, this can happen for scenarios where a specific device was incorrectly or not classified by the Third Party (Device Atlas) which is used to identify Device Type in Analytics reporting and was later correctly classified.
Another scenario where this can happen is when you have implemented Cross Device Visitor Stitching, but if that would have been the case, the difference would have been a significant number and not a mere 31.
It seems that I used the word Rare in a bit wrong context. What I meant was that it can happen with only few devices and hence the magnitude of such issue will be very low.
Also, as Device Atlas regularly update their database, such scenarios are expected to happen now and then. However, if you see a bigger discrepancy you can highlight the issue with Adobe ClientCare by creating an incident with help of Supported users in your organization.
I have an additional question related to this, you said that this difference is due to a rare scenario, but, as in my case, what if this happens every month? Is there a way to solve this situation or should I only ignore that little difference between both numbers?