https://github.com/GhostScissors/RadA-Decoder/releases Download the decoder from this link to convert rada files to wav. I will upload some samples so you can see what this type of file looks like.

rada_sample.zip The rada file is extracted using FModel by saving audio data. If, instead of saving the audio, you export the raw data, you will get a uasset file and a ubulk file. I then examined these three files and ultimately discovered that the rada file is actually composed of the header from the uasset file plus the entire ubulk file. The header has a fixed size of 168 bytes. Simply locate the "ADAR" signature, save 168 bytes starting from this signature, then append the entire ubulk file and write it into a rada file. Finally, use radadec.exe to decode it into a wav file. I have tested this, and hope it helps you.