Zabbix SNMP returns differnt value than snmpget on shell

[AndWei]

Situation: APC UPS, query for the result of the last selft test via SNMP (OID 1.3.6.1.4.1.318.1.1.1.7.2.3.0 | 1 - Passed | 2 - Selftest failed | 3 - Invalid Result | 4 - In Progress)

snmpget returns '1', indicating a succesful self test:

[root@host ~]# snmpget -v1 -c public ups.domain.tld 1.3.6.1.4.1.318.1.1.1.7.2.3.0
SNMPv2-SMI::enterprises.318.1.1.1.7.2.3.0 = INTEGER: 1

Configuration of item in Zabbix

Name	APC: Last Self Test Result
Type	SNMPv1 agent
Key	upsLastSelfTestResult
Host interface	X.X.X.X:161
SNMP OID	.1.3.6.1.4.1.318.1.1.1.7.2.3.0
SNMP community	public
Type of information	Numeric (Unsigned)

Problem: Zabbix stores a value of '0', instead of a '1' like snmpget returns. What am i missing?

The item is not marked as unsuppported, switching the "Type of information" between Int, Float and Text changes nothing. Zabbix still returns '0' instead of '1', Other values like voltage, load and temperature are read and stored correctly by Zabbix.

Addition:
Zabbix server runs on CentOS Linux release 7.9.2009 (Core)
zabbix-release-4.0-2.el7.noarch
zabbix-server-mysql-4.0.34-1.el7.x86_64
zabbix-get-4.0.34-1.el7.x86_64
zabbix-cli-2.2.1-1.el7.noarch
zabbix-web-mysql-4.0.34-1.el7.noarch
zabbix-agent-4.0.34-1.el7.x86_64
zabbix-web-4.0.34-1.el7.noarch

net-snmp-agent-libs-5.7.2-49.el7_9.1.x86_64
perl-SNMP-Info-2.11-2.el7.noarch
php-snmp-5.4.16-48.el7.x86_64
net-snmp-libs-5.7.2-49.el7_9.1.x86_64
net-snmp-perl-5.7.2-49.el7_9.1.x86_64
perl-SNMP-Simple-0.02-3.el7.noarch
net-snmp-devel-5.7.2-49.el7_9.1.x86_64
net-snmp-5.7.2-49.el7_9.1.x86_64
net-snmp-utils-5.7.2-49.el7_9.1.x86_64