Hi all, Seems like every so often the discussion comes up as to whether or not the Vortex is a very noisy unit (I know I've been in the "mine is very noisy" camp before.) Anyway, I recently took my studio apart and re-wired it back together in an attempt so remove some of the hiss the vortex was contributing to the effects loop. I put the vortex into its own send/return so that I could at least control when I added the hiss of the vortex, but before I did this I did a test. Plugging straight in to the vortex and listening with headphones from the output on the back of the unit, the vortex was very very clean, almost no hiss whatsoever. After I got the mixer all wired back up I plugged in through that route and what I discovered was that there was a fair amount of hiss in the signal again. After some messing around I discovered the root of the problem I think. The vortex seems to have a sort of feedback going on that takes any incoming noise (like hum from a pickup or whatnot) and it sends it back through the processor and so on until it becomes really audible. I found that when I switched patches, the noise floor would drop down and then slowly the hiss would start building up as the effect was on for a while. So that's my theory, the Vortex is not inherently a noisy box, but perhaps an overly sensitive one and the nature of its effects will amplify pre-existent noise until its slightly bothersome. Do I have a fix for this? Not really, but now I am more relaxed about the hiss since I know its more a remnant of the guitar* I use rather than the Vortex itself. Maybe every Vortex user already knew this, but I must have missed it in the various go rounds on the topic. Thanks for letting me ramble Kevin *A 65 Fender Mustang that has been known to pick up radio signals and various other sonic anomalies on occasion.