m4v and dts

Do forgive me if this has been answered in the past, but i can’t seem to find a definative answer.

I have my Apple TV conected via HDMI to my TV via my surround sound system. Under Infuse i’ve for both AC3 and DTS passthrough enabled.

If i play an MKV with a DTS track everything plays fine, however with M4V files i am unable to access the DTS track, it’s not that i can’t select the DTS track, it simply doesn’t show up in the audio track list.

Is DTS in an M4V container not supported?

AC3 with either MKV or M4V container works fine.

Thanx for any help