Cup Jams sg200

[Bigybronco]

Hi everyone I have a seaco sg200 with about 3500 vends the machine is great  the problem is  every once and a while the cup won't drop or it partially drops and Jams then goes out of service   I've tried everything I've tried different cup suppliers but but I can't figure it out  I'm not sure if I'm missing something  I noticed the arm has a slight studer as it swing  over for sugar  not sure if it has anything to do any help would be awesome thanks in advance