playback stuttering could be from anything, cpu, app cpu usage in the background, antivirus. does it happen when no apps are running? how does it play in safemode? is it all music formats? it could be your codecs. do you have an intergrated soundcard or seperate soundcard? have you tried older drivers, sometimes newer drivers create issues.
that sound could be caused by:
1. poor audio cable grounding.
2. both the pc and amp plugged into the same powerstrip or receptacle.
the pc power cord has a ground, and so does the reciver, what is created is a ground loop.
Ground loop is a condition where an unintended connection to ground is made through an interfering electrical conductor. Generally ground loop connection exists when an electrical system is connected through more than one way to the electrical ground.
When two or more devices are connected to a common ground through different paths, a ground loop occurs. Currents flow through these multiple paths and develop voltages which can cause damage, noise or 50Hz/60Hz hum in audio or video equipment. To prevent ground loops, all signal grounds need to go to one common point and when two grounding points cannot be avoided, one side must isolate the signal and grounds from the other.
ways to resolve it.
ground loop isolator, or ground loop filter.
if what you're hearing is crosstalk, get better cables or connectors.
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