Hi,
I've been experiencing some noise issues with my UFX and i'm trying to figure whether this is normal, or if there is a problem with my unit, or some kind of grounding issue.

I've had my UFX for about 6 months or so now and I notice that there is pretty audible white noise when I turn the gain up past 30 or so, regardless of whether anything is connected to it or not. When i have the gain up all the way then noise is pretty loud (the meters in TM read -60, and it's about 5 db louder when i engage the Inst button. Not sure it's been there the whole time i've had it but I just noticed it the other day when recording a Blofeld synth module directly into the instrument inputs. I had to turn the gain up because the blofeld has a pretty quiet output and that introduced a good amount of noise that was very audible on the recorded track. It seems like highest I can have the gain before having the noise be too much is around 30-35. Normally I don't have to go past 25 or so when using mics, or DI'ing guitars.

So is this a normal thing that i just need to work around? When the gain is all the way down on the inputs it's dead quiet (TM reads -108). Could it just be a grounding issue? Would connecting the blofeld to a quality DI box (considering buying a Radial JDI) and connecting that to the mic pre help me get louder levels out of the blofeld with less noise? Everything i've read seems to indicate that the DI box should help with noise, but I want to make sure that it's isn't a problem with my unit before I spend money on something else only to find out it doesn't make much of a difference.

I'm using a macbook pro and some passive alesis monitor one's connected to an alesis ra150 poweramp. Issue is the same whether I use usb or firewire, and is identical on all four of the preamps. The noise is there whether the UFX is connected to my computer or running standalone, and is the same on different sample rates.