Hello,

for some time now my Fireface 400 has been behaving quite strangely: oftentimes when I turn the knob (which I almost exclusively use for Headphone Volume) in the counterclockwise direction, it does at first decrease the volume but then suddenly and unexpectedly jumps  to the highest volume setting. My ears do not very much like this, obviously. Also sometimes it's hard to change a volume setting at all; no matter how fast, slow, soft etc. I turn the knob, the volume setting kind of 'jitters' around a certain (mostly way too high) value.
I have read that some people also have had some trouble with the knob (yes, I also tried to pull it out a bit, that, however did not solve it).. So my question here is: is this a known bug to RME? And: how do I deal with it? The unit was bought ca. 15 months ago (in Germany, at Thomann), so should still have warranty. Do I have to send it in? To them or to you?

Thanks a bunch in advance! And a good slide!

- Till

System info: FF 400, v1.70, driver v3.01, Macbook Pro 2011, Logic Studio 9, Powered externally, no further firewire-devices connected