After upgrade to RU7 all types of clients (Unknown, Predefined and Managed) will not follow the Default NBS Settings values (Default Boot Option for specified type of client)
After default Boot Menu Timeout, client will select iPXE Boot menu option and will time-out and select Next Device option
DS 8.1 RU7
This issue has been reported to the Symantec Development team.
A fix is available from KB info5191 'Cumulative Post 8.1 RU7 Point Fixes'.
File name: 'DS 8_1_RU7_Cumulative V1.zip'