Is it normal to hear a bit of static when turning up volume knob on amplifier?

[Trillion]

Hi, I recently purchased a Marantz PM6005 amplifier and I've noticed that if I turn the volume knob up when my optical cable is connected from my PC to the amp, and no sound is playing, I can hear a little bit of static noise through the speakers/headphones. This effect is far less apparent with my Fiio E10K connected via 3.5mm line out to RCA, but this route seems to amplify the sound less anyway. Seems that all sound is about 80% of the volume this way. Is this normal? Thanks

 

[MajorFubar]

Yes.