Satellite Server (spacecmd): xmlrpcfault

Issue

• I am seeing a "xmlrpcfault" using the spacecmd for a Satellite User:-
• Error message:

# spacecmd -u testuser -p <removed> -s localhost system_listinstalledpackages srv01
INFO: Spacewalk Username: testuser
INFO: Connected to https://localhost/rpc/api  as testuser

ERROR: redstone.xmlrpc.XmlRpcFault: No such system - sid = 1000010005

• But with testadmin it works

# spacecmd system_list|grep srv01
INFO: Spacewalk Username: testadmin
INFO: Connected to https///localhost/rpc/api  as testadmin
srv01

• I originally tried with the user: "testuser" as a read-only user and have also tried a s a "normal" user.
• As you can see using our API user (testadmin) works.
• Below is how the users are defined:

testadmin   API User, Application   Organization Administrator, Channel Administrator, Configuration Administrator, System Group Administrator, Activation Key Administrator
-----
testuser        Sec User(normal user)

• Why would a "read-only" or "normal" user not be able to see any systems?