We've been experiencing resolution loss on our 6550 QTOF. It appears as if one ion is being split into two peaks. This tends to affect higher m/z ions and it can be monitored in real-time when zooming in on one of the calibrant ions.
This also appears to manifest itself as drop out during a sample run. The top trace is the TIC and the bottom is the reference ion in MS+.
If you compare the spectra for the reference ion m/z 922.0098 immediately before and after the drop out event you can see the ion is being detected at roughly +/- 50ppm off center. I believe this is the manifestation of the splitting observed in the spectrum data when monitoring it real time.
Has anyone experienced these issues before? We've removed all tune files and performed a full classical system tune to see if possibly this was related to corrupted tune files but that proved unsuccessful.
