Sorry for the vague subject heading, but couldn't think of a better way to put it.
 
So, you know the sound you get if you put your smartphone too close to your monitors? That pitched static sound?  Well, I recorded a podcast recently and to my dismay, that pitched static/interference sound had "gone to tape".  But here's the thing: my cell phone wasn't even in the room at the time, and my monitors were muted.
 
There were two of us in the room, and my buddy did have his cell in his pocket, but it was MY mic that picked up/recorded that interference.  Neither of our mics were pointed directly at the monitors or at each other, although my mic was closer to the monitors than his. (I was using a Rode NT1-A and his was an AT2035.)
 
Funny thing is that I didn't hear any interference at all while we were recording, only after it was too late.
 
This is the first time I've ever run into this and I'm guessing that my mic placement is probably to blame (my mic placement is much different when I'm tracking my own vocals), but now I'm a bit paranoid that it'll happen again.
 
I get that interference whenever I have a brain fart and put my cell phone on my desk, but that's no big deal since it's a monitoring-only situation and I simply need to move the phone out of the way. But now it has shown up in recordings and it's being caused by something other than my phone....any ideas? 

It's not unique to monitors so yeah, you can get it on the recording. Putting cell phones in airplane mode is a good idea while tracking. Or just switch them off altogether.

So you think it might've been my buddy's cell phone that caused it?  (Mine was in another room when we were recording.)  Just strange that his mic/track didn't have any interference but mine did.

That is weird.  You didn't hear the static was monitoring the recording? I have an issue with my MONITOR/Display causing COMPUTER sounds (glitches, hard drive whirls, etc.) over my monitors but not in the recording signal.
 
I have isolated the problem to a MACKIE outboard small mixer that I like to use to manage my monitoring.  But, the sounds do NOT get recorded as part of any live track recordings.
 
Sorry, I couldn't help you directly but the next time you hear some sounds, I suggest you try and isolate the culprit of the noise and then look for a specific solution.
 
Jim

Is this phone interference or a constant buzzing?
 
Phone interference is that hefty brupting when it's communicating with a base station.
 
Constant buzzing tones are a mains earth loop, caused by PC, interface, active monitors, instruments having their own power supplies which result in multiple connections to earth.

Hey guys.
 
No, the interference wasn't audible at all while we were tracking. I only noticed it after the fact when I was playing back the audio.
 
It isn't a constant buzzing.  It's an intermittent, "pitched static" type sound.  In the past, whenever I've heard it, it's when my cell phone was sitting on the desk, so I'm assuming that's what's causing it. But because my phone wasn't in the room and my mic picked up the interference but my buddy's didn't (and he had his phone in his pocket) I'm wondering if it's something else.
 
I DID recently swap out my old mouse for a wireless one...could THAT be causing it?

streckfus:
 
Can you post a snippet of the sound?  Someone might be able to identify it from the characteristics of the audio.
 
Also, depending upon what your monitoring source was, you may have missed it because you were monitoring at a point in the signal chain that was before where the interference was being injected in the signal that was being recorded.  Could that be why you missed it when you were recording?
 
Paul

Yeah, good call.  I'll upload a sample to YouTube after work today and provide the link.
 
I was monitoring through headphones connected to my interface, so it's really strange that I didn't hear it while monitoring.  Both mics plugged into the interface, direct monitoring from the interface.
 
Of course, I suppose it's entirely feasible that the oddity was present while we were tracking and I just didn't notice it because I was focused on the podcast conversation instead...one disadvantage of being engineer and performer at the same time. :)
 
But in either case, I've only noticed it before through my monitors when my cell phone was in close proximity. This is the first time the interference was actually recorded.

I have never used this but I think there is an audio tool that let's you sample noise and then based upon the sampled noise, eliminates it from a targeted track.  (I might have dreamt this but somewhere in the way back machine I might have stumbled upon this).
 
Jim
 
PS - it might have been a noise reduction tool in Soundforge but not sure

Is it possible the XLR cable has been damaged so that it is no longer balanced? What I find most odd from your description is that the direct monitor didn't catch it. That almost implies the interference was created in the interface->PC cable, or possibly in the PC itself.

Another thing to try would be check an input echo from SONAR back out to the headphones.