High pitched whine from BDVN5200

[KieranCork]

Hi guys,

Recently got the BDVN5200 which I think is the same as the BDV-N5200w and overall it has been pretty good. Quite often, during certain shows, they are high pitched noises especially during laughter, and even more epecially during the laugh tracks during "The Big Bang Theory"

It is really annoying. 

There don't seem to be any firmware updates and rebooting the system does not cure it.

Any ideas?

Thanks.