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- Oct 25, 2019
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So- I made the mistake of spring cleaning and re-organising my AV rack yesterday. Today whilst using the RME with some sensitive IEMs I had a noticeable (assume 60hz or thereabouts) hum. So I started doing some testing. Observations:
1. Touching the join between the device and the IEM jack stops the hum
2. Hum present regardless of source selected (USB or Toslink)
3. Hum present with nothing other than IEM connected to RME
4. Hum present when RME in standby
5. Hum present if I move the RME to a new room, on its own into a power socket away from anything else.
6. Touching any of the empty metal sockets to the rear stops the hum.
7. Physically lifting the RME stops the hum.
So its a ground loop right? But why now, why with nothing else connected? Have I damaged something during the spring clean? Power supply issue?
I have deployed a temp fix- connected the unused coax jack to another (unused) device thats grounded- as long as I keep the other device plugged in on standby- no hum.
But something aint right, surely?
Any suggestions? Am I missing something basic but fundamental? Little bit concerned if I wanted to relocate the RME to a new location without the ability to connect to something grounded (eg my home office/ dining table) I will be hummed at.
Any help appreciated. @MC_RME ?
1. Touching the join between the device and the IEM jack stops the hum
2. Hum present regardless of source selected (USB or Toslink)
3. Hum present with nothing other than IEM connected to RME
4. Hum present when RME in standby
5. Hum present if I move the RME to a new room, on its own into a power socket away from anything else.
6. Touching any of the empty metal sockets to the rear stops the hum.
7. Physically lifting the RME stops the hum.
So its a ground loop right? But why now, why with nothing else connected? Have I damaged something during the spring clean? Power supply issue?
I have deployed a temp fix- connected the unused coax jack to another (unused) device thats grounded- as long as I keep the other device plugged in on standby- no hum.
But something aint right, surely?
Any suggestions? Am I missing something basic but fundamental? Little bit concerned if I wanted to relocate the RME to a new location without the ability to connect to something grounded (eg my home office/ dining table) I will be hummed at.
Any help appreciated. @MC_RME ?