I also have a Sandisk 200gb card from Amazon.ca. I loaded everything on, about 125gb. Works fine in my Opus 1s. Loses 1/3 of album covers and about 10% of files on the Hiby r3. Let's face it. The Hiby is buggy, underpowered and sounds awful. Burn in is an urban myth sorta like spending hundreds for connecting wires and earphone cables. Wire is wire. Electronics either work or they don't. Have fun trying to make this thing try to work for you. Mine is for sale.
I have a 400gb Sandisk with over 9000 files and all files play and all album art works. I admit Album art is a bit slow to update.
I'm not a believer in electronics burn in. If it does then somebody prove it