snmpget authentication failure error...?

Hi All,
 
When I enabled snmpd on my target board. and tried testing with snmpget
I am getting error saying that 
 
ObjID: SNMP-USER-BASED-SM-MIB::usmStatsWrongDigests.0
 
Can any body help me out for what is the reason  for this error.
 
Here with I am pasting a part of output after executing snmpget.
 
snmpget -v 3 -u myuser -l authNoPriv -a MD5 -A my_password 192.168.31.14
system.sysUpTime.0 -c brcm -D ALL
 
trace: snmp_pdu_parse(): snmp_api.c, 4151
dumph_recv:         VarBindList
trace: snmp_pdu_parse(): snmp_api.c, 4181
dumph_recv:           VarBind
trace: snmp_parse_var_op(): snmp.c, 151
dumph_recv:             Name
dumpx_recv:              06 0A 2B 06 01 06 03 0F 01 01 05 00
dumpv_recv:                ObjID:
SNMP-USER-BASED-SM-MIB::usmStatsWrongDigests.0
trace: snmp_pdu_parse(): snmp_api.c, 4190
dumph_recv:             Value
dumpx_recv:              41 01 11
dumpv_recv:                UInteger:    17 (0x11)
trace: _snmp_parse(): snmp_api.c, 3941
snmp_parse: Parsed SNMPv3 message (secName:myuser,
secLevel:noAuthNoPriv):
trace: snmpv3_get_report_type(): snmp_api.c, 3840
report: Report type: -35
trace: snmpv3_get_report_type(): snmp_api.c, 3840
report: Report type: -35
snmpget: Authentication failure (incorrect password, community or key)

Thanx in advance.
 
Regards,
Raghavendra. S