HomematicIP: Multi-actuator 'hmIP-DRBLI4' not visible as entities in homeassistant

Hi everybody,
I am running RaspberryMatic on a Raspberry Pi 3. A supervised homeassistant instance is running in a Docker container on a different Raspberry Pi 4. I am using the homematic integration (https://www.home-assistant.io/integrations/homematic/).
In Homematic I have three devices: HmIP-RCV-50 (Virtual Remote Control), HmIP-BROLL (Homematic IP Blind Actuator for brand switch systems, flush-mount) and HmIP-DRBLI4 (Homematic IP Blind and Shutter Actuator for DIN rail mount - 4 channels). The integration in homeassistant is working and using this config:

homematic:
  interfaces:
    hmip:
      host: 192.168.178.29
      username: !secret raspberrymatic_username
      password: !secret raspberrymatic_password
      resolvenames: json
      port: 2010
  hosts:
    raspberrymatic:
      host: 192.168.178.29
      port: 2010
      username: !secret raspberrymatic_username
      password: !secret raspberrymatic_password

My issue is: There is only one entity visible in homeassistant and it is coming from the HmIP-BROLL device: cover.shutter_bathroom_hmip_broll_d431
Both other devices do not show up at all. Interesting behaviour: I added the homematic integration to the logger component:

homeassistant.components.homematic: debug
pyhomematic: debug

What I can see there is that the other devices are well communicated to homeassistant:

2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic._hm] RPCFunctions.createDeviceObjects: created 0025DA49A76201  as SUPPORTED device for HmIP-DRBLI4
2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic._hm] RPCFunctions.createDeviceObjects: adding to self.devices_all
2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic._hm] RPCFunctions.createDeviceObjects: adding to self.devices

and:

2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic.devicetypes.generic] HMGeneric.__init__: device_description: 0025DA49A76201:0 : {'TYPE': 'MAINTENANCE', 'SUBTYPE': '', 'ADDRESS': '0025DA49A76201:0', 'RF_ADDRESS': 0, 'CHILDREN': [], 'PARENT': '0025DA49A76201', 'PARENT_TYPE': 'HmIP-DRBLI4', 'INDEX': 0, 'AES_ACTIVE': 1, 'PARAMSETS': ['MASTER', 'VALUES', 'SERVICE'], 'FIRMWARE': '', 'AVAILABLE_FIRMWARE': '', 'UPDATABLE': True, 'FIRMWARE_UPDATE_STATE': '', 'VERSION': 1, 'FLAGS': 1, 'LINK_SOURCE_ROLES': '', 'LINK_TARGET_ROLES': '', 'DIRECTION': 0, 'GROUP': '', 'TEAM': '', 'TEAM_TAG': '', 'TEAM_CHANNELS': [], 'INTERFACE': '', 'ROAMING': 0, 'RX_MODE': 0}
2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic.devicetypes.generic] HMGeneric.__init__: device_description: 0025DA49A76201:1 : {'TYPE': 'MULTI_MODE_INPUT_TRANSMITTER', 'SUBTYPE': '', 'ADDRESS': '0025DA49A76201:1', 'RF_ADDRESS': 0, 'CHILDREN': [], 'PARENT': '0025DA49A76201', 'PARENT_TYPE': 'HmIP-DRBLI4', 'INDEX': 1, 'AES_ACTIVE': 1, 'PARAMSETS': ['MASTER', 'VALUES', 'LINK', 'SERVICE'], 'FIRMWARE': '', 'AVAILABLE_FIRMWARE': '', 'UPDATABLE': True, 'FIRMWARE_UPDATE_STATE': '', 'VERSION': 1, 'FLAGS': 1, 'LINK_SOURCE_ROLES': 'WINDOW_SWITCH REMOTE_CONTROL CONDITIONAL_SWITCH SWITCH', 'LINK_TARGET_ROLES': '', 'DIRECTION': 1, 'GROUP': '', 'TEAM': '', 'TEAM_TAG': '', 'TEAM_CHANNELS': [], 'INTERFACE': '', 'ROAMING': 0, 'RX_MODE': 0}
2020-07-20 11:26:55 DEBUG (Thread-2) [pyhomematic.devicetypes.generic] HMGeneric.__init__: device_description: 0025DA49A76201:2 : {'TYPE': 'MULTI_MODE_INPUT_TRANSMITTER', 'SUBTYPE': '', 'ADDRESS': '0025DA49A76201:2', 'RF_ADDRESS': 0, 'CHILDREN': [], 'PARENT': '0025DA49A76201', 'PARENT_TYPE': 'HmIP-DRBLI4', 'INDEX': 2, 'AES_ACTIVE': 1, 'PARAMSETS': ['MASTER', 'VALUES', 'LINK', 'SERVICE'], 'FIRMWARE': '', 'AVAILABLE_FIRMWARE': '', 'UPDATABLE': True, 'FIRMWARE_UPDATE_STATE': '', 'VERSION': 1, 'FLAGS': 1, 'LINK_SOURCE_ROLES': 'WINDOW_SWITCH REMOTE_CONTROL CONDITIONAL_SWITCH SWITCH', 'LINK_TARGET_ROLES': '', 'DIRECTION': 1, 'GROUP': '', 'TEAM': '', 'TEAM_TAG': '', 'TEAM_CHANNELS': [], 'INTERFACE': '', 'ROAMING': 0, 'RX_MODE': 0}

So I think there is some issue that prevents the integration from creating the neccessary entities in homeassistant. Since all the device data comes along the interface from homematic, I doubt the bug is there. Does anybody have any ideas?

Best, Daniel