The thermally-generated (incandescent) light from the Sun is pretty much white noise, I believe, if you had an antenna ~500 nm in size to translate it in the same way we translate "regular" radio waves to sound. That's about as "complicated" as a waveform gets.

(Note that such an antenna, and suitable tuner and carrier elimination, is easily manufacturable with modern chipmaking technology. Just that there is no non-fun, economically-justifying, reason to build it, particularly the latter two parts - I believe such nano-antennas have already been tried for other purposes. [On the other hand, maybe someone like MrBeast or other mega YT influencer could fund it FOR fun!])