Strange blank baseline

Hi All, 

We recently installed an 8890GC/5977C MSD with TDU back inlet. For the first time post installation we switched from back inlet to front inlet and noticed a drastic drop in sensitivity as well as shifting retention times than we previously had in the front inlet. Additionally, any blanks we ran had a strange baseline of siloxane although the relative abundance was low. Please see attached photo. I'm not sure what could be causing this issue, could it be improperly cut column or something else?

Thank you!


Was this helpful?