Humming and crackling sound

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi everyone,

I am facing a problem with my audio system right now. I have a digital source that is directly connected to an amplifier. The sound volume of the audio system is controlled using the digital volume control of the digital source.

The problem is that I am hearing a constant low frequency humming noise coming out from my speaker and occasionally a rather loud crackling spark sound will be emitted (from one or both speakers). All these equipment is plug into a star-earth power distribution plug. From what I understand so far, the signal ground of the digital source and the amplifier are both floating.

I also noticed that when I place one finger at the shield of the RCA cable and another finger at the chassis of the amplifier, the humming sound will reduce at least by 50%. I will also feel a slight tingling sensation in my fingers when I do that. I am not sure if this piece of additional information is helpful.

What can be done to remove this humming and crackling sound?

Thanks.
 
Last edited:
Thanks asmith! :)

I tried swapping the existing RCA cable with a new one but the problem is still there.

I am using a 3 prong power cord (UK version) for all my equipment. I tried swapping all the power cords one by one with a brand new power cord but the problem is still there.

I tried "connecting" different parts of the chassis with my fingers (using my thumb and my index finger), there is no such tingling sensation. The tingling sensation only arise when I touch the shield of the RCA cable and the chassis.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.