Poll: What is your optimum listening time?

[ffaux]

I get angry and feel frustrated all the time when I listen more than 9 or so hours. 9 hours is borderline, 8 hours is preferred. I experimented whilst on Stress Relief and found that I was getting stressed so I lowered the volume slightly and decreased the hours from 18-21 hours per day slowly down to 12, then 10 and then 8 and found that I only felt good when I reduced it down to 8.

Part of the answer for me might be that the speakers are 1m from my head on either side and the volume at the source hovers around 30db so it's probably really intense already which allows me to listen less hours.