Upstream power

Hi,

I have a 2-way splitter installed by comcast (Antronix 2-1000 mhz) for TV and cable modem use.
My Motorola SB6141 upstream power is 47-49 on 3 channels, and a steady 50 on the fourth channel. Downstream SNR and power good on all 8 channels.
I understand that a 50  is a concern, what can be done to lower it?

Thanks
Daniel