Pues nada chicos me he puesto en contacto otra vez con panasonic porque parece que escuchan, les comente lo de los negros y como veis han arreglado por lo menos el modo THX. Esto es lo que les he escrito, supongo que a vosotros tambien os interesara que arreglen e implementes estas cositas:

Hello, I want to give feedback about the last firmware 1621 model Panasonic TX-P42GT50Y, updated today. I report a problem with the black levels with the firmware 1619 (it´s explained in the first mail I sent to you). Well, now with the firmware 1621 the black problem has been corrected but only in the thx modes. If you select and compare the different modes in a dark room with a black screen, cinema and professional modes still have less black level compared to standard dynamic and thx. As I say thx black levels has been corrected in the last 1621 firmware so thanks!

The last thing is about controlling the volume of an audio system with the Tv´s remote. This steps are from my old sony Bravia. It´s an easy and useful thing but the Pansasonic plasma 2012 is´n capable of that (I mean the AV1 audio out). I think it would be easy to implement it in a future firmware update.

In the sound setting menu, select [Audio Out] using the / buttons, then press the button.

Select [Fixed] or [Variable] using the / buttons, then press the button.
Select [Fixed] to adjust the volume using the connected audio system’s remote. Select [Variable] to adjust the volume with the TV’s remote when using an external audio system.

Thanks for great TV´s and thanks for listen us.