Narrative:

During cruise flight approximately 50 to 60 miles east of fix and offset 5 NM right of course; as directed by ATC; [ckeck pilot] and I were discussing the procedures for approach and runway change going into ZZZ. I had selected the route 2 page; neither of us activated or executed the route 2. During the discussion control called us and ask our position; and then we immediately noticed the aircraft in a slight left bank; approximately 20 degree bank; and our heading approximately 40 degrees of expected. PF (pilot flying) immediately slowed and selected a correction heading back to course. I estimate we erred off course 3 to 4 miles before correcting. I did not notice what the to waypoint was before we were recleared back to zzzzz. I am sure that we were in LNAV and correctly proceeding to zzzzz before the event.I am not sure if there was a failure of the navigation system but both [pilot flying/check pilot] and I were heads down too long discussing runway change procedures and not monitoring the aircraft and systems. More diligent aircraft monitoring by both crew members [was needed].

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Original NASA ASRS Text

Title: B767 Captain reported that the aircraft was briefly off course causing Center to alert the deviation.

Narrative: During cruise flight approximately 50 to 60 miles east of fix and offset 5 NM right of course; as directed by ATC; [Ckeck Pilot] and I were discussing the procedures for approach and runway change going into ZZZ. I had selected the route 2 page; neither of us activated or executed the route 2. During the discussion Control called us and ask our position; and then we immediately noticed the aircraft in a slight left bank; approximately 20 degree bank; and our heading approximately 40 degrees of expected. PF (Pilot Flying) immediately slowed and selected a correction heading back to course. I estimate we erred off course 3 to 4 miles before correcting. I did not notice what the to waypoint was before we were recleared back to ZZZZZ. I am sure that we were in LNAV and correctly proceeding to ZZZZZ before the event.I am not sure if there was a failure of the navigation system but both [Pilot Flying/Check Pilot] and I were heads down too long discussing runway change procedures and not monitoring the aircraft and systems. More diligent aircraft monitoring by both crew members [was needed].

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.