Optical (TOSLINK) to RCA for DTV

[slekvak]

Hi

I'm having troubles using a Optical (TOSLINK) to RCA converter for sound output to my home theater system. All is well for HDMI sources, but when using DTV (enabled by a CI module), sound isn't working, I only get distorted "sparkling". All channels say "HE-AAC". I've seen similar threads on different models where this is seemingly solved by enabling PCM. I do not have any settings for this, as far as I can tell.

Model: UE40B6050VW (40A1UF0E / UB6000)
Firmware: T-CHL5DEUC-2010.1

Any way to solve this? Through the service menu?