Hello friend, i am 99% sure that the problem lies with the emulator type.
You see, there are 2 main types of Dingoo A320s, Pawed and UNpawed.
(See the back of your unit for the "paw print" logo, or the lack of it to verify wich one you have.)
Now, there are at least 2 emulators that are unit type specific, meaning that one will work for one type of A320 and the other for the other type.
The 2 that i know well of in this case are the GBA and the Odyssey 2 emulators.
I would post the links to them both, but it's been awhile, and I have since lost the sites.
I have both versions of the emulators.
Sometimes for the GBA emu, the corresponding config. data helps.
If you would like, you can send me a pm and i will forward them both to you so you can try them both and fix this issue.
This is concerning the Native OS by the way.