I had been messing around with the custom tune settings on my GC-QQQ trying to pass a DFTPP tune check without completely destroying my sensitivity. While I was looking at my last several tune reports, I noticed that my max gain factor has started dropping pretty dramatically. I know it's normal for it to drop over time but I don't know if it's normal to drop so quick.
In April after an Agilent PM, it was around 7 million.
In Mid-August after having hardly used it for several months, it was 1.4 million.
It stayed around 1 million for awhile, and was about 0.9 million on 9/15.
On 9/18, it dropped to 0.6 million.
Today, I tried re-tuning from default values (to counter any tweaking from trying to compromise between sensitivity and DFTPP), and it's 0.4 million.
I realize that it's still plenty high, but it seems to be dropping pretty quickly. Does anyone know if that is normal?