IGMP Querier behavior on Mgmt VLAN

Hello

I am facing a behavior in the area of IGMP snooping/querier which I do not understand and therefore would be thankfull for help. I've got the following setup:

Core Switches:

    - 2 independent M5300-82GF3

Access Switches:

    - 1 M5300-28G3 Stack (2 switches)

    - 1 M4100-12G-POE+

    - 1 M4100-D12G

    - 1 M4300-28G

They are all linked together using MST, the MGMT VLAN is 30 on all switches. The core switches act as gateways (VRRP) as well as running L3 IGMP on all VLANs they are participating in. Not every switch is participating in all VLANs but of course in VLAN 30. The core switches do not habe IGMP Snooping enabled but all the others have. The others also have the "Querier Admin Mode" enabled globaly. Every access switch has the VLANs it participates in added to the "Querier VLAN Configuration" table BUT ONLY one of them is enabled. This is actually the VLAN which is unknown to the core switches (so far).

What I see is that for all the VLANs the core switches participate in and have L3 IGMP active on them, one of them is being elected as querier which makes sence and is what I want. BUT there is one exception, the MGMT VLAN. The access switches acctually do participate in the Querier Election on VLAN 30 eventhough the Querier Election Participate Mode is set to disabled on all of them.

I do not get why they're participating in the election process. Because it only happens on the MGMT VLAN I gues it has something to do with the fact that it is the MGMT VLAN. Even more interessting, I configured the "global" "Snooping Querier Address" to be one out of 1.1.1.XYZ on all the access switches and left the VLAN specific settings at the default (0.0.0.0) but the switch being elected as querier in the MGMT VLAN is being shown with its actual MGMT interface IP address on all the other switches.

Attached you can see a screenshot taken from one of the core switches having the MGMT VLAN marked.

So, what am I missing here?

Best

dialsc