Inclined Baseline on Samples

[BSCChem]

In our lab we are measuring trace chloride content of a particular compound and until recently we have been getting a incline in our baseline only when we run samples and in our blank. We experimented with different suppressor settings and nothing changed. Below are the parameters and any suggestions would be greatly appreciated.

Dionex DX-500 Ion Chromatograph
-Ionpac AS10Column, 4 X 250 mm (P/N 043118)
-Ultra ASRS Suppressor, 4mm (P/N 061561)
-Ionpac AG10 Guard Column, 4 X 50 mm (P/N 043119)
-Eluent: 100 mM Sodium Hydroxide

[Chris Pohl]

It appears that you are working under isocratic conditions. Is this correct? If so, can you elaborate on what you observe in terms of background? If you run two samples in series does the background resume where it left off on the previous sample?