Not sure if this is the right sub to ask, but I've recently gotten the Fosi IM4's and the SMSL r1 dac/amp. Now the im4's work fine on their own when plugged into laptop, phone or pc. The r1 however does play sound through the iems when plugged into any device via usb-c (iems through 3.5mm jack at the front of the r1), but there's this very loud static noise coming through the iem, that isn't there when not using the r1. The noise is still present on other headphones, but a little quieter. The led volume indicators on the r1 also only light up at max volume. The sound coming through the r1 also doesn't sound good, very canny/hollow.
So my question is, is this a problem with the r1, the im4's (I doubt it), or the devices im using?
Ps. I'm new to this kind of stuff :)