TSC indicator showing tubes that have low current, but tubes check out ok

I really need some input regarding this safety monitoring function in the Grandmeister Deluxe 40 amplifier.
My first head that I got, only worked for an hour, and the TSC lights all came on. Needless to say, I thought that I got a lemon and sent the head back to the store. I then got the new one. I truly love the tone and functionality of this amp, but reliability has been a big concern for me. Since I have gotten the new head, I have had many little issues. The amp will crackle out at least once every gig, and then when I reboot the amp it has made it through the remainder of the show. I have played about ten gigs with this head, and now the TSC indicator is showing a problem with the two center Tubes. The two middle lights will stay illuminated regardless of the power soak setting. I have swapped the tubes, and the lights do not change. I am wondering if maybe the anode fuse for those two tubes has possibly blown or if this could mean something else. The tone seems a bit fuzzy ever since this started, but otherwise it seems to be still working right.
The wattage seems to be doing what is supposed to when I switch from 20 to 40. Hopefully someone could shine some light on this for me.

I started having a lot of problems with mine making lots of noise even in stand by mode. I swapped out those Chinese power tubes for electro harmonics and that solved all problems. Been working flawlessly ever since.

I have tried all groove tubes from another amp and it still does the same thing. Thank you for that reply. I am pretty certain there is something else going on here. There are also times where it wont work at all and all the lights come on.

Hi Meman.  Sorry to take so long to reply but I've just got back from a couple of weeks in Greece with no good online connections.  It was bliss!  But no guitars.  It was Hell!  Still, can't have everything can you?  I did come across a very nice taverna out there with a board hanging on the wall which really made me laugh then think.  It just said, "We don't have Wifi here.  TALK TO EACH OTHER!"  I just forgot you guys at that point and concentrated on my wife.  

First bit of info, there is only a single anode fuse so with one pair of valves working it must be ok.

That amp "crackling out", (I know what you mean), is not usual but is generally down to a faulty valve or valves somewhere in the chain.  Have you tried swapping out the preamp valves as well as the output ones?  It is possible that one of those is crapping out and causing the crackling as a separate issue to the TSC lights.  Valve replacement of those original Chinese is not strictly necessary, some people secretly even prefer their sound, but I think many of us find now that as soon as most of them are out of the picture the amp settles down valvewise.  The only real reason to consider keeping one is in the V2 position where there is often a direct coupled cathode follower.  That circuit configuration eats up valves at a rate of knots and Chinese valves like Shuguangs for example have been shown to be much more resilient to the type of abuse that circuit gets.  That would mean leaving the other Chinese triode in V2 in place as the third gain stage though.

One easy thing to do here is to perform the "TSC plectrum test".  Do that and let us know what the flash count is and we can see if that gives us any more info.  It is possible that it will show the output valves are fine and the problem is somewhere else or maybe one of them is working but just way way out of whack.

You could also try doing a factory reset of the software, making sure to back up any patches/voices you have created and stored first of course as these would be lost during the reset.  It's not likely to be the root cause of all of this but again, it can't hurt to have the amp back in pristine new condition as regards its control programming.


EDIT: I should add, is your speaker cabinet wiring and your speaker lead beyond question? A stray whisker of copper in a socket or plug can do dastardly things just like you are hearing.