Encrypted Query locking server from time to time
Looking at what you posted, it's most likely an Agent job trying to insert data into a table in msdb clashing with an Agent job trying to select data. 

This can take a long time, especially if you've never cleaned up Agent job history. These tables can get quite large and contentious on old or busy servers. 

Have a look here (full disclosure, it's my company's blog): https://www.brentozar.com/blitz/msdb-history-not-purged/