core/homeassistant/components/channels/icons.json

{
  "services": {
    "seek_forward": {
      "service": "mdi:skip-forward"
    },
    "seek_backward": {
      "service": "mdi:skip-backward"
    },
    "seek_by": {
      "service": "mdi:timer-check-outline"
    }
  }
}