Enigma2 (OpenWebif) - setting the source (channel)

Configuration
1

I have loaded the Enigma2 (OpenWebif) integration and can use a media-control card to turn the box (Beyonwiz V2) off, set volume & select a source (a TV channel).
The configuration.yaml is :

# Beyonwiz V2
media_player:
  - platform: enigma2
    host: 192.168.1.13
    name: q-V2Wiz
    use_channel_icon: true
    mac_address: d027xxxxxxxx
    source_bouquet: '1:7:1:0:0:0:0:0:0:0:FROM BOUQUET "userbouquet.favourites.tv" ORDER BY bouquet'

However, I can’t work out how to set a source/channel from an automation. I’ve tried the following without success :

- id: '1681287670044'
  alias: Set ABC
  description: ''
  trigger: []
  condition: []
  action:
  - service: media_player.select_source
    data:
      source: ABC TV
      media_channel: ABC TV
    target:
      entity_id: media_player.q_v2wiz
  mode: single

Tried with & without media-channel and with & without quotes on the “ABC TV”. Any suggestions ?
(HA 2023.4.2 in Docker container on Synology NAS)

2

After much fruitless trial & lots of error, I re-tested the yaml above (without the media_channel line) & it works. No idea why it didn’t work initially.