Sorry for bringing back an ancient thread.
So for a while I thought it was maybe isolated to the single piece of gear I was using and avoided using that piece of gear as a HW insert, but now I am doing some further testing and it is showing up on ALL of my outboard gear... every single piece -- I just never noticed it as much in the past and for whatever reason, it is much louder on the one piece of gear aforementioned. Have to really zoom in on the waveform to see it elsewhere.
I tried patching in a loopback cable on all ins and outs on my UFX+ -- no ticks there. It also doesn't show up when patching a passive 600:600 transformer in between the UFX+ ins and outs (through patchbay)
Again, only at 88.2 kHz and 96 kHz, and not 44.1 kHz or 48 kHz at all.
Should also note that the noise also appears with nothing plugged in to the input of the gear (from the RME Line Outs or elsewhere), and doesn't go away if patching things like isolation transformers between the output of the gear and the RME Line Input.
As a result, I am lead to believe this is not an ADC or DAC issue and still some sort of "packet noise"....
The ticks show up when the unit is connected via USB and also when connected via Thunderbolt BUT the ticking over Thunderbolt is *slightly* lower noise than over USB.
I should also note that changing the buffer size DOES affect the spacing of the ticks. Setting it around 64 samples or 128 samples is roughly 770~ measured samples in between ticks where as 1024 or higher is around 820~ measured samples between ticks.
Here's an image of a recording in Izotope RX. This one is actually worse, with the ticks extend down to 12khz:
And this is the initial piece of gear, again. The ticks extend from 48khz (limit) down to around 20.5khz:
if I really turn up the gain on a compressor chain, it'll extend all the way down to 8khz. THIS particular screenshot is with the Line Output from the RME going into the first piece of gear and then output of the last piece of gear returning to the RME Line Input. Disconnecting inputs from the first piece of gear dramatically lowers the noise, but same ticking is still present on the waveform:
I tried pulling every single USB peripheral out of my computer other than the UFX+ (and my iLok so I can run Pro Tools) and recording that -- no change. Tried UFX+ on a every different USB port / bus on my computer -- no change.
Have tried the UFX+ and the computer on different power outlets, even different circuits in the circuit breaker. Different line conditioners, no line conditioners, surge strips, etc... even plugged the UFX+ (and likewise computer) over long extension cables into completely different rooms... no change, still ticking. (though moving the UFX+ over to a higher end Tripp Lite line conditioner lowered the noise floor...)
]Tried an entirely different patchbay, cables, and likewise running the gear directly in and out of the UFX+ line ins/outs without any patchbay in between -- no change.
And again, still occurs using the I/O of my Ferrofish Pulse 16 MX in the same configuration, and when clocking the RME UFX+ to the Ferrofish over MADI.
"Ticks" might not be the correct word to describe this, but not really sure what else to say about it.