Hi. I am using GC-MS 7890. The instrument was switched off for a few days due to lockdown. Now, I run the std alkane and terpene std. So the intensities of peak especially for RT was lower than what I had previously observed in single quad GCMS. The alkane std did show peaks that are much broader and lower in intensity in single quad GCMS. The terpene std showed three broader peaks where the compounds were not resolved in single quad GCMS.