At night, I play calm, low-volume cricket sounds for my sun conure and parakeets. They love it. I keep it running on their own mp3 player when it's light out.
For the random day time, I may play wind, river, frog, jungle noises, choral music, etc. I have a whole collection (over 3,000 files) on the pc that I just rotate on the flash drive which gets hooked to the player. That way, there's always something new / different.
When there are loud fireworks, I run all the electric fans for white noise + crickets to calm them.