Dialnorm on DTS HD-MA???

[odin24]

I've noticed on a few BDs (all with 24 fps, opposed to 23.976), have dialnorm applied to the DTS HD-MA, always -4dB when dialnorm is present. All are European BDs too, I have not seen dialnorm on NA releases.

I was just wondering why there would be dialnorm, when there usually isn't on DTS HD-MA.

Thanks.