comware 7 unable to connect on snmp v3

i have both comware 5 and comware 7 HPE 5500 series switches and both are configured for SNMP v3 

snmp-agent
snmp-agent local-engineid 800063A20344319216818F

snmp-agent community read hp5500read

snmp-agent sys-info contact <Me>
snmp-agent sys-info location <here>
snmp-agent sys-info version v3
snmp-agent group v3 v3authpriv privacy
snmp-agent usm-user v3 snmpadmin v3authpriv cipher authentication-mode md5 <encrypted PW> privacy-mode aes128 <encrypted PW>

when i test with Solarwinds SNMPWALK the comware 5 switches connect to fine, but when i test any of the comware 7 switches they come back with :

snmpv3 - wrong digests - the authentication digest did not match the expected result, possible incorrect key/password (0;))

i have re-added the last line above, carefully retyping the correct password for both entries knowing this is correct as it works on the comware 5 switches but unfortunately i cant fathom out what might be different between comware 5 and 7. 

Thanking you in advance for any assistance you may be able to give.

Rob