Hello,
The Tascam 1x2HR is working very well as USB A/D source in Volumio! It also offers the ability to detect signal clipping (on its front panel) and consequently adjust the preamp accordingly. It is also the only USB ADC sound card I’ve found with RCA line in input. It is built like a tank and all this for for less than 100€.
Some follow up though : Volumio states (on the play screen) the source is 48kHz 32 bits whereas it is in fact 192/24.
Is it a display bug or a real thing? As I wanted to pass the turntable signal through Volumio to benefit from the DSP feature (convolution), I do not want the DSP to be fooled by a wrongly detected frequency / bit rate.
If there are some test to be done to clarify this or some Config to be made to set the frequency / bit rate manually on this Volumio input, I would be happy to know 
.