New Service SB6141 Issue

I had service installed about a week ago for the 50 mbps down HSI.  I own a SB6141 modem.  I am still seeing speeds that are 31Mbps down and 11 Mbps up.  This is run off the cox speed test site using a direct connection to the modem.  I spoke with customer service and got to a tier 2 rep who couldn't resolve the issue.  I specifically asked about the "Premier for DOCSIS 3.0" setting for my account and he stated that it was set correctly.  He checked the firmware on my modem and stated that it was 1.0.6.12 but that Cox did not have firmware for this modem and I had to manually update it from the Motorola website.  The Motorola customer service stated that only my ISP could update the modem firmware and they would not provide it.  Any help would be appreciated.