INTERACT FORUM

More => Old Versions => JRiver Media Center 27 for Windows => Topic started by: curiousMonkey on November 03, 2020, 06:21:15 pm

Title: LFE hum when Theater view is displayed
Post by: curiousMonkey on November 03, 2020, 06:21:15 pm
This is a really strange problem. Recently I noticed that I could hear a low level hum in my room when I was using MC27 but not playing music or watching a movie. I was able to locate the hum in all three of my subwoofers. The main speakers are almost completely silent but definitely don't have the same hum coming from them.

If I exit out of Theater View in MC 27 (hit ESC), the hum goes away.

Here is my configuration:
MC27 configured with 5.1 output for audio.
HTPC with NVidia GT1030 card for HDMI.
Marantz 7703 with 5.1.4 speaker configuration
The LFE output goes to a miniDSP which controls 3 separate subwoofers.
All subwoofer connections are RCA and the cable lengths vary from 10 to 40 feet.

The most recent change in my configuration was adding the GT1030 video card to replace the embedded Intel GPU.
Title: Re: LFE hum when Theater view is displayed
Post by: JimH on November 03, 2020, 06:28:00 pm
Theater View uses 3D drawing.  Could be related.
Title: Re: LFE hum when Theater view is displayed
Post by: wer on November 03, 2020, 06:32:35 pm
That is indeed strange.

Can you confirm that this hum does NOT occur when using the HDMI out from your motherboard integrated graphics whilst running theater view?

Try this as a test: Change your audio output device in MC to something other than the NVidia card, like the analog outs on the motherboard, or something like that.  Then launch theater view.  Does the hum still resume?

If yes, my guess would be that activating the GPU (which theater view does) is causing interference in the NVidia card, which is manifesting as spurious data in one of the audio channels. The remedy would be to replace the defective card.  If no, then more pondering will be necessary.
Title: Re: LFE hum when Theater view is displayed
Post by: Gedeon on November 04, 2020, 02:18:13 am
Those issues are hard to solve. Power issues, ground loops, non perfect isolation ....

My system has the same issue. When "high current" is running through videocard/GPU you can eve "hear" when disks are spinning, ... and a hum...