hi Mathias,I'm having the same problem, and have been browsing through the forums - apparently we are not the only ones. maybe we can group all of these threads into one larger "POD HD PRO startup" problem thread?

Maybe you can have a look at this thread http://line6.com/support/thread/88492 in which I describe my problem. As you, I've also done complete firmware updates or refreshes, including wiping all my presets, but problem remains.

So I would like to know if you always start up your unit with the guitar cable plugged in? I noticed that sometimes "resetting my global parameters" (startup with navigation button pressed to the left) seemed to help, as well as setting all my preset inputs to global (guitar + mic) instead of using "preset". Since I guessed that the problem must somehow be "guitar input" related, instead of starting up with my guitar plugged in, I start up the unit, and let it complete its startup cycle completely before I plug in my guitar. I've just started doing that the last few days, and so far, that seems to solve the problem (fingers crossed - I've only started up about 5 times without problems, so hope it stays that way).

Since you, as well as Texxx had this problem with TWO units, maybe it's because we all start up with the guitar cable plugged in (PS: Texxx, in case you are following this thread, I would like to ask you the same question: did you also start up with the guitar plugged in).

If you do, can you startup without the guitar plugged in, wait a bit (30 seconds) and plug in to see if that helps. If we can find a "common" denominator to this problem, Line6 can do something about it. Maybe a high input signal from a high-output humbucker during startup triggers some kind of "protection mechanism" in the unit (to keep the output levels below a certain threshold or something?)

@ Line6

I don't know if this problem is known to you, but I think at least 10 people on this forum have mentioned this same problem. Are you guys looking into this, or do you consider this a "hardware glitch" in some pod hd pro's (because I think that this is not the case...). Since I also have a HD Bean and a HD500 in which I always leave my guitar cable plugged in, I do think it's only related to the PRO model (al my patches are exactly the same on all my units, with guitar + mic input setup, since that's the only common input method to all three POD HD's, if you want to use only one guitar input signal) - I have no problems on the HD500 and the Bean.

Maybe it's some kind of "input level" protection on the HD PRO guitar input connector that has been set differently for the HD PRO? I do hope you manage to find a solution. Maybe you can reproduce the problem by starting up a HD PRO, and during the startup cycle already start playing with a guitar with a high-output humbucker. Since some threads mention that version 1.3 of the firmware doesn't seem to give the problem, I think you should look at your implementation of the new "variable impedance feature" that was introduced since firmware 1.40. At the moment I can still use my PRO, but sometimes this problem seems to get worse, and since I bought this as a secondhand unit (four months old, so almost new), I suppose I'm now without warranty, so I do hope this can be solved with a firmware fix....