It could be many things. 1  Gather facts. 2  Rule out equipment... 3  Back to gathering facts... 4  Call Comcast.  Good 1  luck. Have your problems always existed (with your current installation/configuration)?  When speaking with anyone...
A maximum-phase system is the opposite of a minimum phase system. A causal and stable LTI system is a maximum-phase system if its inverse is causal and unstable. That is, 1  The zeros of the discrete-time system are outside the unit circle.
In phase means that the AC voltage and current vary together in time; when the voltage reaches its peak so does the current, and when the voltage is zero, so is the current. The instantaneous current is always proportional to the instantaneous voltage.