[mythtv-users] Eliminating a ground loop/hum

[David Snider]

Don't know if this helps, but I had the same problem with my  
Digimatrix.  Turned out to be the audio input from the CDROM.   
Disabling (muting) it in Alsamixer fixed it.

On Jul 5, 2006, at 9:24 PM, Owen Mehegan wrote:

> I have a new Myth system that I've just built. I'm using an MSI  
> PM8M-V motherboard, with its on-board audio (Via VT8233/A/8235/8237  
> AC97) for everything. The system is connected to a Sony 34" CRT TV  
> using DVI/HDMI cable. Audio is routed as follows:
>
> cable box -> myth box -> tv -> Sony home theater receiver/speakers
>
> All of that is done via basic RCA cables. My problem is that I have  
> an intermittent 60hz hum in the audio. I hear it whether I'm  
> watching TV or just in the Myth interface. Playing with various  
> mixer volumes doesn't make it go away, in the sense that I can't  
> null it out without having the whole system's volume down too low  
> to hear anything. I have everything plugged into one power strip/ 
> wall outlet, and the outlet has three prongs; whether it's really  
> properly grounded or not is anyone's guess. I tried unplugging  
> various unrelated components (Xbox, cable box, cable modem/router)  
> and got no change.
>
> So, any suggestions on what I should do to clean up this audio?  
> Maybe buy a better sound card? (And use spdif out while I'm at it?  
> My receiver can handle it, though it's a pain in the ass from a  
> "management of the available inputs" perspective.) What if I bought  
> a UPS and plugged everything into that? I've seen suggestions of  
> "home theater" magical grounding thingys... if you think one of  
> those would help, a link to a specific product would be sweet. Thanks!
>
> --
> owen at nerdnetworks.org (Owen B. Mehegan)
> 'Therefore, since brevity is the soul of wit,
> And tediousness the limbs and outward flourishes,
> I will be brief.'
>   --William Shakespeare
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mythtv.org/pipermail/mythtv-users/attachments/20060705/272aaff4/attachment.htm