An update for all who is interested.
Yesterday received a replacement set (including the speakers)
Initially replaced the AMP on the faulty speaker but no joy..
Means that the actual speaker was messed up.
Replaced the whole unit (speaker and AMP) and then noticed that the right rear speaker was having a little crack in sound as well.
Whilst everything was open already i replaced that whole unit as well and now all is perfect.
As i see it.. i have at least 1 good AMP for sale and one unit where either the AMP or the speaker is lost (anyone interested??)
Regards,
Marc.