A day after transit advocates and frustrated subway riders rallied outside Governor Cuomo's Manhattan office demanding that he devote more resources to improve the subway system, the MTA had another rough morning, with "significant delays" and overcrowding reported on multiple subway lines.

Signal problems at 36th Street in Queens caused delays on the M and R lines, as well as changes to E and F service. An earlier incident at 125th Street resulted in delays on the 4, 5, and 6 lines. A train with mechanical problems at Bergen Street in Brooklyn caused delays on the F and G lines. There were signal problems on the northbound A line at West 4th Street.

But this morning's aggravating commute also served as a reminder that not all subway delays are the MTA's fault. Police activity around 8 a.m. at Jay Street-Metrotech forced northbound A trains to terminate at Nostrand Ave, while some downtown A trains terminated at Chambers Street. An NYPD spokesperson said an unidentified man in his 50s was found unconscious and unresponsive on an A train at the Jay Street-Metrotech station. He was pronounced dead at the scene.

The ensuing delays on the A and C lines were extensive. Reporter Scott Heins stood on a crowded C train at Kingston-Throop Avenues that did not move "for half an hour" before giving up and going to the street around 8:30 a.m., along with many other frustrated commuters. One straphanger said the train was ultimately taken out of service. (A and C train service has since resumed, with delays.)

Frustrated straphangers also spilled out of the Nostrand Avenue stop at Fulton Street as train after train terminated there. The nearby B25 bus stop overflowed with riders headed to Downtown Brooklyn for alternative trains.

Ashley Foy, 24, waited on the platform at Nostrand for over an hour before following the pack up to street level. "All of a sudden everyone got off the train. On the train they said that it was going out of service. I actually don't know what I'm doing," she said. Presented with the various train option, she laughed. "So: Uber."

The MTA is reminding commuters this morning that they can always get proof of their subway-related tardiness from the MTA:

You can also just shoot your boss a link to this Gothamist post; totally official.

With Emma Whitford.