Sunday, good time to post here ... despite the current 2nd and big wave of Corona building up here in Europe (Germany in my case). Stay healthy, everybody!
This is a little heads-up on using an SD card with Qobuz, in particular for importing music in order to listen to offline.
I had formatted my new Samsung Extreme Pro microSDXC 1 TB as FAT32, directly on the N6ii‘s Android 8.1. This formatting is non-default, i.e. it got shipped with exFAT, and Windows would only put an exFAT onto it. I had decided to use FAT32 as a precautionary measure due to
Your 400GB Ultra should work, but if you encountered any problem such as skip tracks, you might need to format it into FAT32. We have received several reports saying that those faster card (160MB/s or above) in exFAT playing back Hi-Res file might causing problem occasionally, we suspect this is related to buffering speed of our DAP but we can't replicate the problem repeatedly.
I use Qobuz for streaming, and I wanted to import a couple of albums for offline listening. Qobuz stores such files in a format known from YouTube, .exo files (Google), where each track is stored in chunks of 2 MB files, encrypted. All such files are placed in one directory by the Qobuz app. Depending on audio resolution, the number of chunk files is much larger than the number of tracks, easily 10 to 100-fold or more.
I had read up on the limitations of FAT32 beforehand, but this didn‘t prepare me for what happened in Qobuz. When my imports crossed the 32 GB mark, i.e. more than 16,384 files, things went bananas: Import downloads failed, the imported music couldn‘t be looked at, even the entire Qobuz app would crash at some point. Actually, I have not seen any limitation on the number of files per subdirectory like this small number, but maybe I‘m mistaken.
So I went back to the default and formatted the SD card as exFAT using Windows. I made double-sure to check the limit on files per subdirectory. Starting my imports all over again - all file system issues are cured. I am at some 36 GB now, more than 18,000 chunk files in that particular directory on SD; these are just 30 or so albums.
Thus, if you plan on doing such a - maybe silly - thing in Qobuz as I do, import quite some albums for local storage, be advised to use exFAT formatting for your SD card. Nota bene: No experience on my side available yet on the issue talked about by Andykong in the quote above.
Furthermore: Why this ”maybe silly“ remark? I notice that it takes an awfully long time to read this particular import directory after booting the N6ii, either in the Android file manager or in Qobuz. And I am not even at 10% of the albums I wanted to import in Qobuz... Does anybody with more Android knowledge than me know how the SD card and this particular import directory gets read right away when switching the N6ii on? What I am doing right now is navigate to this directory in file manager, and ask it to display the properties, then wait...
But then, maybe I need to get more used to the fact that a DAP just is not a computer, and not even a state-of-the-art phone (like my iPhone X) regarding IT capabilities ...