Having a strange problem when I select the DAC input on my Preamp. There is a hum (or more of a hiss) that stays on for 20-30 seconds then it goes away by itself. So before I can do much experiments with disconnecting/ unplugging equipments to see what's causing it, it just goes away by itself.
If I keep everything on and dont play any of the components, the hum sometimes comes and goes. But usually goes away completely after I start playing music. My DAC has a CD player and Chromecast audio connected to it. There is no such problem when I switch to the turntable input. I even connected an ifi AC purifier but didn't help.
Can any of the forum members give me some advice on this?
The only change I made was introducing an online UPS in the room which is connected to an outlet that doesn't have any HiFi equipment connected to it, only the chrome cast audio. The UPS is strictly for the TV and the Bluray player.
If I keep everything on and dont play any of the components, the hum sometimes comes and goes. But usually goes away completely after I start playing music. My DAC has a CD player and Chromecast audio connected to it. There is no such problem when I switch to the turntable input. I even connected an ifi AC purifier but didn't help.
Can any of the forum members give me some advice on this?
The only change I made was introducing an online UPS in the room which is connected to an outlet that doesn't have any HiFi equipment connected to it, only the chrome cast audio. The UPS is strictly for the TV and the Bluray player.