I managed to swap out the 4gb card with a 32gb card on my RS-97 i have made a quick guide below if anyone else want’s to try it as well.
(REPLACE 4GB CARD WITH HIGHER CAPACITY CARD)
Step 1 Download the firmware here https://mega.nz/#!JIBVDaDa!K1IrPbrjHrdiXQOX9w2b-EAB9n7GHFeQkE084R-cBiQ
Step 2 burn the image file to your new micro sd card using this https://sourceforge.net/projects/win32diskimager/
Step 3 Expand the Fat32 file system using this https://www.disk-partition.com/free-partition-manager.html
Step 4 Open your RS-97 carefully and remove the micro sd card then insert the one you just created and close back up.
Step 5 It should boot and use the full storage available on the fat32 file system as you can see in the pics below enjoy.
