After 11 years of broadcasting on RR, I decided I want to hear the audio I'm sending to broadcastify so I added a speaker adjacent my scanner to hear the scanner audio real-time using 3.5mm splitter. The new splitter (also tried various brands) or some conjunction of new cabling creates a hum on the feed audio. Remove the splitter and it's cabling and the hum goes away. The only way I get rid of the hum is going back to the single line-in feed without the splitter.
I tried 3 different splitters and 3 unique audio cables thinking it was a hardware issue but all present the same sound. And I verified the cable is pushed all the way in to the female so the connectors are not rubbing. Any variation of these cabling creates a hum on the line. I broadcast on Raspberry Pi's so I also tried HDMI cables with an even worse result. I then tried a line-out cable to hear the audio after it has been processed by the Pi, but that too creates a hum. I use Darkice but don't see that as an issue since the hum disappears when I unplug the cabling. All powered devices are fed through a grounded server rack so I don't see grounding as an issue.
I found a rather old forum mentioned a ground loop isolator. I don't hear the hum without the splitter. Would a ground loop isolator help in this case? I have 3 separate feeds with the same issue so is there a hub isolator or would I need 1 isolator per feed? Any advice is welcome as I prefer keep the feed audio output as clean as possible.
I tried 3 different splitters and 3 unique audio cables thinking it was a hardware issue but all present the same sound. And I verified the cable is pushed all the way in to the female so the connectors are not rubbing. Any variation of these cabling creates a hum on the line. I broadcast on Raspberry Pi's so I also tried HDMI cables with an even worse result. I then tried a line-out cable to hear the audio after it has been processed by the Pi, but that too creates a hum. I use Darkice but don't see that as an issue since the hum disappears when I unplug the cabling. All powered devices are fed through a grounded server rack so I don't see grounding as an issue.
I found a rather old forum mentioned a ground loop isolator. I don't hear the hum without the splitter. Would a ground loop isolator help in this case? I have 3 separate feeds with the same issue so is there a hub isolator or would I need 1 isolator per feed? Any advice is welcome as I prefer keep the feed audio output as clean as possible.
