Replacement Sanyo SF-P101N 16 pin laser on Cambridge Azur 640C

Very strange fault on this player. Processor intermittently mutes audio due to mistracking. This has been happening for years, because original flex ribbon was worn out and had a break. Because there are no servo adjustment in this unit, I decided to replace the mechanism and purchased one from WES Components. Sadly, the replacement unit which is hopefully an original Sanyo unit does not read CDs. Sometimes even when you pay 3 or 4x the eBay price, they still do not work...