samba - Mar 2018 - What does a domain member authentication failure mean?

I am running Samba 4.4.16 on an AD/DC server. I have several Linux domain
members. Occasionally
(not every day) I get a message in the samba log like this one:

[2018/03/05 17:57:31.690032, 2] authentication for user [HPRS/OHPRSSTORAGE$]
FAILED with error NT_STATUS_WRONG_PASSWORD

I understand when I get such a message when a user enters the wrong password,
but OHPRSSTORAGE
is a domain member computer hostname.  I get this sort of message occasionally
for all the
Linux domain members, but never for the Windows domain members. 

Why?

THX --Mark