I’m experiencing this very weird beep which randomly (usually with a maximum interval of 5 minutes between occurrences) comes out when connecting my guitar to the PC through my M-AUDIO MTrack II Plus audio interface.
I’ve done TONS of tests, in which I tried pretty much everything…: Getting my phone away from the room, taking down the power supply of the apartment, changing jack/signal cables, audio interfaces, buildings (I live in an apartment building) and even CITIES…
Below are the results of my tests:
- Software doesn’t seem to be involved, as I can hear the beep also if I set the audio interface to “direct”, routing the signal flow from the guitar input directly to the speakers/headphones, without passing it through the PC.
- PC hardware doesn’t seem to be involved, as I can hear the beep using my laptop and a friend’s desktop PC too
- Musical Instruments doesn’t seem to be involved, as I can hear the beep just plugging one end of the jack into the audio interface and leave the other one unplugged. Although I noted that the beep doesn’t seem to occur when connecting my microphone (which uses an XLR cable), but it is coming back if I only connect one end of the XLR cable to the audio interface and leave the other one unplugged
- Changing Audio Interface doesn’t seem to affect the situation: I tried the Focusrite Scarlett 2i2 (3rd Gen) audio interface and beep still occurs.
- Changing cables doesn’t seem to affect the situation: I tried either my “not so well shielded” jack cables and cables which should be shielded better like Roland ones and beep still occurs. I also tried to connect my audio interface to the PC with this cable with ferrite chokes but nothing changed. The only weird - as much as “weird” means in this VERY WEIRD issue - thing I noticed about cables is the one I described above about hearing the beep when my mic’s XLR cable is disconnected from the mic and not hearing it when connected
- I tested the setup also in another apartment within the same building, in an apartment within another building in the same city (just about 50m away from my home) and in an apartment within a building located in another city about 33km away from mine, finding out that I can hear the beep in the other apartment within my same building and in the apartment 50m away from me; while I don’t hear the beep in the apartment in the other city
- As I said, the beep seems to come out randomly, everything I was able observe was that it usually comes with a maximum interval of about 5 minutes between occurrences. I also noticed that in the night it seems to happen less frequently, there were a couple of times when I tested at 2/3 A.M. and didn’t hear any beep for about 10/15 minutes
- Of course, keeping my phone distant from the audio interface (e.g. another room of the house) doesn’t seem to matter, beep still occurs. The same happens taking down the power supply of the apartment, still hearing the beep
- As suggested in this topic I also tried to download the “Ultimate EMF Detector RealData” app in my phone and I scanned for EMF values the area of the desk where my audio interface is placed and found a value of about 20 microTesla. However, I don’t know how reliable this measurement is, as it seems to change a lot after very small movements (we’re talking about centimeters) within the same area of the desk and considering that the value of the measurement increases greatly when I bring my phone closer to the right side of the audio interface, thus reporting a value of around 24 microTesla when I place the phone on the left side of the interface and values up to 170/180 microTesla when I place the phone on the right side of the same interface. What’s even stranger to me is that these values are detected even when the interface is not connected to power at all.
Looking at all these tests the issue seems to be some sort of interference, but I couldn’t understand the nature of the interference and how to avoid it… I hope you can help in this because I'm not really figuring out anything…
3,334 Hz,8,000 Hz(Strangely precise) and10,667 Hz. There is also a seemingly temporally related anomaly at100.2 Hz, which is also strangely precise.