I developed software to work the RSP1A with a Raspberry Pi 4B using the v0.7 SDRPlay image. It runs fine on my RPi4B (4G) that I bought a couple years ago. I just tried it on a new RPi4B (4G and 8G) and the working SD card does not boot at all. On one device it got far enough to say it needed newer software. On the other two I get nothing.