So my question is can audio that I stream on a Sunday sound better than the same music during the week? Is it possible that you get less bandwidth when things are busy during the week versus when there’s less traffic on a Sunday?
That's an interesting question. Bandwidth does have a huge impact on quality. HD was originally intended to be High Definition- one channel of ultra high quality audio and video. Until the suits figured out they could stuff 500 channels of I Love Lucy and weather reports into the same pipe as just one HD movie. Streamers could be doing something like that.
But, I rather doubt that is the reason. Because they would need some reason to be going back and forth. Bandwidth costs, they aren't streaming for charity. More likely its just you are noticing what others have mentioned, its the power.
There's a simple enough test. You already hear the difference streaming. That could be bandwidth. Now try CD, or records. If those also sound better, well then its not bandwidth.