A couple quick switches this week...
Successfully figured out the C code to control the volume on the RDA5807. The Bass Boost feature refuses to work. It could be that the documentation is borked. At this point, I'm giving up as going further means writing code for features I don't use. Will post what code I have on Github shortly.
Started working on getting the Si4707 weather band breakout board working. Like the others, it's becoming a "learning experience". The documentation claims that it can be driven into 2-wire mode, using the same method used for the Si4703. I've missed something as the chip still doesn't show up on the I2C bus.
I'm hoping to have the Si4707 figured out quickly as an entire evaluation kit for the Si4735 (think FM, AM, and short wave) was waiting for me when I arrived home. This one will take a lot of research. The code that comes with it is for Windows, the board interface is USB, and I'm not sure if I can piggyback a Pi onto it (fingers crossed). Will let you known when I start playing with this.