Comment 9 for bug 1688696

It's interesting that GIO reports the correct value (that's where your file browser, which I assume is Gnome Files, gets its values from). Can you double check to confirm that Gnome Files displays the correct disk free and total bytes value?

In this instance, both Python and Qt are failing to determine the correct value, which may mean that GVFS is not supplying it correctly to them. That's my guess at least. (Rapid Photo Downloader currently uses Qt to get volume usage; Qt is likely making the same library call as Python).