I have been having the same problem over a month too. Astoria NY too.
I never had this problems when I had the 25 mbps tier. All my speed problems started when I upgraded to 50mbps/6mbps at the end of November last year.
Encoded Mac: 0da356710e0287693ba52084071147c656fba1bd
Modem Mac: [Removed]
Downstream Limit: 53000000
Return Frequency: 30700000
Upstream Limit: 6300000
Forward Frequency: 687000000
Forward Modulation: qam256(4)
Ret Channel Width: 6.4Mhz
Reboot My Modem Downloaded: 33MB in 60 seconds