Hi, I just bought US-16x08 and wanted to do some test 16 channel recording to see how much better signal to noise ratio is compared to my 20 year old PCI soundcards (Sek'd Sienas). After arming tracks for recording with nothing connected to interface inputs, I noticed that monitoring peakmeters are showing very high noise flor. All mic preamp gain pots are on minimum, inputs 9-10 are in line mode, other line-ins are +4dBu. Signal to noise ratio varies, depending on the channel, from -62db to -86db (my PCI cards connected to Spirit live mixer inserts are steady from -78db to -80db). I recorded a short sample of silence in 16bit/44.1kHz and normalized each track - attached screenshot shows how much gain it took to normalize the recording in each channel. Frequency analyser shows peak in very low frequencies, and that may be the culprit (I attached screenshot of one track soloed). I did some more tests with microphone connected (preamp noise swamps mic noise), phantom power on/off, DSP/mixer disabled, 24bit/96kHz resolution, and there's no significant change (except maybe that in 24/96 there are resonances at (4,)8,16,24,32 & 40kHz on channels 13-16 ~12db above noise floor). Is all this normal for this interface?