Short answer:  SMPTE (cinema/Dolby) and WASAPI (Windows) use different channel‑order standards, which is why Center and LFE/Sub appear in different positions — even though the channel meaning is identical.


WASAPI / Windows (WAVEFORMATEXTENSIBLE)

Windows defines channel order strictly by bit position in the channel mask:

  • Bit 2 → Center

  • Bit 3 → LFE  

So Windows 5.1 order is: FL, FR, FC, LFE, SL, SR

SMPTE / Cinema / Dolby

SMPTE DCP metadata defines 5.1 order as: L, R, C, LFE, Ls, Rs  

This looks similar — but the index positions differ. In SMPTE, Center is channel 3, LFE is channel 4. In Windows, Center is channel 3, LFE is channel 4 only if you count from 1, but internally the bit positions are reversed (Center bit = 2, LFE bit = 3).


In Tide16, the system will automatically probe this information from the incoming stream and toggle to the correct channel assignment. 


Note however that in some cases, one might want to hardcode this behavior so it's by default using the default Wasapi configuration. You can do so from the web user interface : ip_address:5050  and under the settings tab


To run in WASAPI mode (e.g. REW measurement with WASAPI assignment). Disable the swap and Force the behavior. 



Once the measurement finalized, make sure to return to the default automatic behavior as such: