Sony TV appears on/off repeatedly

Hi, I’ve had set up my Sony Bravia TV and was able to operate this with HASSIO (read status, set channel, on/off, etc.) However now it seems that the TV can no longer be operated and the ‘history’ shows the TV toggling on/off. The issue seems the same as the one below:

Anyone facing this issue? As I’ve just switched from local access to remote access via DuckDNS I’m think that there might be a relation.

This I found in the logging:
2019-01-23 22:35:19 ERROR (SyncWorker_13) [braviarc.braviarc] Exception: HTTPConnectionPool(host=‘’, port=80): Max retries exceeded with url: /sony/audio (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x6f53c8f0>, ‘Connection to timed out. (connect timeout=10)’))
2019-01-23 22:35:19 ERROR (SyncWorker_13) [homeassistant.components.media_player.braviatv] ‘NoneType’ object has no attribute ‘get’

The other network media device (e.g. receiver, media PC, Ziggo box) are still working properly in HASS

I seem to have ‘solved’ this by connecting via LAN instead of WAN.