Generally I fly SID to STAR in the longitude and activate APPR mode at the FAF at the published altitude.
I have a similar issue that may me related.
I have the GS and Loc but yet, with HDG and ALT off, the longitude will not lock on at least 50% of the time.
When it does lock on, my last dozen or so flights, the plane flys a few degrees off course. If you don’t disengage AP, a miss needs to be taken. Same thing happens on the next approach. Wind is not the issue. The plane is off course.
Only thing that I can think of, a couple weeks ago I updated MSFS with the new 1204 AIRC Navigraph database.
Could that have shifted ILS / runway alignments?
I am using the new WT 6.2 update, but 6.1 did the same thing.
Other ideas?