WSUS changing Update Source on its own

We have 2 WSUS Servers and ConfigMgr. A week ago, one of the WSUS servers began changing the Update Source on its own, no changes had been made. 

It began pointing to the ConfigMgr and when changed back to use MS Update, shortly after checking again it reverted back to use ConfigMgr. Checked all Events, checked the SQL SUSDB for the WSUS server however there was no information related to this action. Any ideas where I can look next ? Thank you