Digital cable length- SPDIF vs AES/EBU- 1.5 meter for either?

Speaking of digital, several years ago a buddy came over to hear my system , listened a while and got up and pulled the power-cord from my internet modem/router . Sound went from very good to live music !
Also put a heavy blanket over my TV which was not near the system. Not as big a deal but a slight difference .

Thanks for your post jl35 . Nice to know I'm not the only one .
 In my system the difference is NOT subtle ! Might be a function of living
 in a condo where the whole place is on same wires, but lot of people are in that situation ,