I have pulled some CAT6 through the ceiling from one room to a nearby cupboard, for line level audio signal.
I haven't used a balun or DI box, and there isn't TOO much hum and hiss, it's manageable.
But something strange is happening with the audio from Alexa, it sounds really bad: a lot of hiss and distortion. When you turn the volume down, the signal to noise is so bad that the hiss is really high, also the distortion doesn't really disappear it just gets quieter.
When I unplug the Alexa and swap it out for audio from my phone, it sounds really clean. So you'd think it's a problem with the Alexa. But...
- I tried another Alexa and the same problem happens.
- I turned the Alexa up (and mixer input down) and vice versa, this didn't help
- So then I plugged the Alexa directly into the amp and it sounds really good
- I plugged the Alexa back and tried it in a battery pack, rather than into the USB power supply, and the problem is still there.
What is the reason for this?
Should I be using baluns, or a DI box or something like that?
I've heard it's fine sending line level signals over CAT6 - indeed with the phone plugged in, it's all good.