I have done some searching and from what it seems if you boot Rock Band 2 from a USB loader it causes problems with DLC stored on an SD card (but works fine with stuff on the NAND). From what I have found there are a few workarounds:
1. Load is from a Disc (either with cIOSCorp, Modchip or Original Disc)
2. Save DLC to NAND, then move in SM to the SD Card (tho this isn't practical since when it is moved back in game each song stays on the NAND)
3. Just don't use DLC
4. Run a loader that supports NAND emulation and have the emulated NAND on the SD Card, unfortunately I believe cIOSrev14 is the only that supports that feature and USB instruments don't work (or at least I can't get them to).
I just wanted to make sure that no advancements have been made since recently since most of the topics I found were a little old. Also what is the exact reason this doesn't work, I assume it has something to do with the cIOS that the USB loader uses not having full control of the SD card in the way it expects. Also #2 GH5 will/does have DLC streaming directly from the SD card (doesn't swap it back and forth to the NAND), does this work when using a USB loader or does it have the same problems.
1. Load is from a Disc (either with cIOSCorp, Modchip or Original Disc)
2. Save DLC to NAND, then move in SM to the SD Card (tho this isn't practical since when it is moved back in game each song stays on the NAND)
3. Just don't use DLC
4. Run a loader that supports NAND emulation and have the emulated NAND on the SD Card, unfortunately I believe cIOSrev14 is the only that supports that feature and USB instruments don't work (or at least I can't get them to).
I just wanted to make sure that no advancements have been made since recently since most of the topics I found were a little old. Also what is the exact reason this doesn't work, I assume it has something to do with the cIOS that the USB loader uses not having full control of the SD card in the way it expects. Also #2 GH5 will/does have DLC streaming directly from the SD card (doesn't swap it back and forth to the NAND), does this work when using a USB loader or does it have the same problems.
Wait 
