Modem performance and modem selection.

“None at all.  See: buffer”. I am somewhat in the dark when you mention buffer.  I did a search on “buffer” and found numerous discussions.  Most talked about using an active buffer in the chain.  Is that what you are referring to?  If so, what brand/model do you recommend?  If not, can you help me understand what you mean by “buffer”.  Thank you 

Streaming is not a very good alternative to CD transports, sound wise, I understand. 

The output of your cable modem is likely ethernet, so isolated at some level. The power supply would also likely be an isolated 2 prong class-2 supply. Not perfect, but pretty good.

Modem - Router - Some audio equipment. To Miller’s point, all buffered, so you are either getting it, or not, and it will be bit perfect (which the CD may not be .. but likely is).

Thank you all for the help...If there are any other comments they will be greatly appreciated By J.