Trouble with rising anion baseline, looks like column bleed?

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I am having an ongoing issue with my anion chromatography where the baseline is rising with my concentration gradient. System is an ICS-5000, AS17C column, 0.25 ml/min, KOH gradient from 0.85 to 51.5 mM, 32 mA current on suppressor. Analyzing ultrapure water for anions in the 5-20 ppb range.

The increase in background conductivity is reminiscent of GC column bleed. Here, however, the analyte signal is not riding on top of the baseline, it appears that the increase in background conductivity is rather sitting "on top" of the analyte, masking the analyte response.

Photo of chromats comparing a standard from a month ago to the same standard today:

https://ibb.co/v4Rt6TN

I have tried replacing the suppressor, guard, gradient mixer, and CR-TC trap thus far. None of these components have resolved the issue.
That's what happens when I ramp up too high also. I start at 23 mM and only go as high as 34 mM. The baseline still rises but it comes down fast enough when the eluant goes back to 23 mM. Any higher and the baseline won't come down before the next injection.
Well, this is not normal behavior for suppressed ion chromatography. If you look at the blue chromatogram in the photo I posted above, that is what we should be getting. There should not be any baseline rise if the system is working properly.

It is also noteworthy here to point out the decrease in sulfate sensitivity between the blue and black chromatograms I linked above.
It is what my IC has always done in 10 years of use. I wish I could ramp higher because I have to get phosphate off the column and it takes 35 minutes at 23 mM. If I ramp to 34 mM at 12 minutes -after the anions I care about come out - phosphate comes off in 25 minutes. If if I didn't have to worry about phosphate I could have 12 minute injections instead of 25 minute. I did talk to people from Thermo about it and they never told me that it was a malfunction in the system.

Let me know if you come up with something. I would love to ramp higher and shorten my injection time. Actually right ow I am not even allowed to ramp because my bosses who know nothing about IC are micromanaging and not allowing it until a new SOP is approved. That's been ongoing for months. If you look at my other posts you will see the turmoil at my lab. The rising baseline is the least of my worries.
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