As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HEADING SELECT KNOB AND HEADING BUG ARE INTERMITTENTLY OUT OF SYNC WHEN ATTEMPTING TO SELECT A HEADING. GROUNDED - YES. VERIFIED SELECTED HDG WILL INTERMITTENTLY PAUSE & THEN JUMP A COUPLE DEGREES AS HDG IS ADJUSTED. SAME RESPONSE WITH EITHER FCC A OR B AS MASTER. REMOVED & REPLACED MCP. OP CK NORMAL. REF B737-800 MM 22-11-34-400-801 & BITE GROUP #49. HGS RTS NORMAL.REF SMM 34-36-00. NINE TAGS INSTALLED & REMOVED.