Speakers sound brighter at evening / night?

I don't know if anyone has noticed this or studied time of day and perception of sound. But for me, I've found in darker environment especially at night my speakers all sound brighter? A few other hypothesis:
1. Power is different at night 
2. My ear is different at night
3. Lighting is affecting perception of sound 
4. https://www.prnewswire.com/news-releases/the-human-brain-is-sensitive-to-light-breakthrough-findings...
"The study shows that we have brain cells that react to light when exposed directly. These results are encouraging, especially for bright-light therapy channeled via ear canal direct to brain tissue", summarized professor Seppo Saarela, PhD, head of  the biology department and leading the research at the University of Oulu.