Why the media servers disappear for a NBU client that is already configured

Hi,

I have a strange problem with the Netbackup 7.5.0.4 version. Frequently I observed that some of the clients in Netbackup doesnot have media servers in the servers list even though the media servers are configured earlier. This is not repetitive for all the clients. Because of this problem on a daily basis some of the backups will be in running state but no data backup rate progression. I heard this is a bug.

Is this true, if so will that be fixed in the next release?

Thanks,

Thiru