As already mentioned in the the discussion from "LED Noise":
I have a noise problem with the internal microphone when sampling. A high pitched whine can be heard throughout the recording which gets louder when raising the input gain:
Could you guys please test if the noise levels/patterns on your device are the same?
I recorded the sample with the OP-Z sitting on my lap, with maybe half a meter of distance to my annoyed face.
In the videos I found online, the sampling quality of the devices seems so much better than mine, which makes me wonder if I have a defective unit.
Have you tried to do that at a completely different place? Maybe there is some strong source of EM interference that is being picked up (but as I said in the other thread this is more likely to be digital noise from the OP-Z itself).
Yes, I already walked around with it as if it was a geiger counter Unfortunately the interference stayed the same. I also think that the source might be the OP-Z itself.
Years ago I had a similar problem with an OP-1. The noise went into the microphone signal and it even changed depending on what the OP-1 was doing (each operation had its own ‘noise footprint’)
Since there wasn’t a lot of activity on this thread and I need to make my decision on keeping or returning the device, I ordered another OP-Z to have two devices for comparison.
Long story short: The second device’s microphone input is much cleaner. I can’t hear any whine and made the same recording test:
What this means is good and bad at the same time:
Good: I am happy (and feel a bit better about my purchase, since the noise really bugged me and made me think about returning the device.)
Bad: This also means that the quality variance of the OP-Z is huge and buying a new one is a game of luck.
I will inform TE support about this and return the faulty device to the seller, explaining the situation. As much as I love these products, the quality control has to improve!