I have a CR-5400 Dual slot adapter. I have 2 32GB Class 10 cards that I know are legit. Still formatting with my PSP, only reads them as a 29GB card. I've read articles, reviews, and seen videos of this phenomenon being true, but am failing to replicate it myself. I have a PSP 2000 with M33-6 Prometheus 4 flashed as the firmware. So how do I do it? Do I need specific firmware or something? Nvm. Strikethrough/keep original post for the sake of google knowledge. I suspect that ADATA cards are thinner than other MicroSD cards. Before I bought 2 ADATA 32GB microSD cards, I had also owned 2 ADATA 16GB cards and two AmazonBasics 16GB cards. I'd always get the Amazons to work in my dual slot adapter, and always had problems with my ADATAs. The fact that I had the same formatting trouble formatting the new cards like I did with the old ones, while the Amazons worked fine is my reason to believe the cards are just too thin to make a consistent connection with the contacts. Shuffling my ADATAs in and out several times finally got me able to format 59GB. I removed the card(s), reshuffled, got 29, removed cards, reshuffled, No Card detected, shuffled again a few more times, 29, 29, 59, 29, 59, 59, etc.... Just a little info if anyone uses google trying to format to 64GB. Using a frail, cheap adapter with ADATA cards may/probably is a contact issue.