Now, though...
And a reader left this in the comments:
The noise is a high pitched sound that sometimes sounds like a whine and at present more like a shriek that varies in pitch. It's affecting people in the upper stories, especially at the rear of buildings on the eastern half of 9th and 10th Streets between B and C. It continues 24/7 for days at a time. It first began last Thanksgiving and returns intermittently. The latest episode has lasted more than a week and those of us affected are getting pretty desperate, as the sign indicates. Calls to 311 have got us nowhere so we've now appealed to CB3 to use their influence with the DEP. As the sign indicates, we can't trace where the noise is coming from but it's most likely a ventilation system.
