Hi! First, let me say that I am a happy and experienced user of REW. I mostly use it with a MiniDSP 2x4 to room correct and provide EQ for Bose 901s, currently with a DIY subwoofer. I've come close to EQ-ing to my house curve (another concept I learnt here at HTS).
What is odd is the past few days' measurements often showed what seems to be a constant tone just above ambient noise, that shows up in waterfall and (my preferred) spectrogram. While not shown, even a sweep of just ambient noise. My current data set has "lines" for 80, 90 and 180 Hz. The 90 Hz has been the most frequent. I cannot figure out the cause, if any. :scratch:
It is worth noting that my living room is open plan, but appears to have modes including at 45 Hz. Am I seeing some odd type of resonance? In any event, these don't seem to interfere with REW's job of making a good EQ measurement.
Here is a link to where you can download my mdat file, if so inclined, to see first hand what I speak of