With the scenario you describe, it is the Blu-ray player doing the decoding - suggest you check the Blu-ray settings once more, there may be other settings concerning secondary audio that may be interfering etc, you need to look beyond just the PCM setting.
If you are sending multichannel PCM correctly into the HD621 - the fact that it is DTS HD is no longer relevant as far as Meridian is concerned.
As above, double check the blu-ray player settings if other formats work OK through the HD621.
John
808v6, M60, MC200, HD621, Lumagen XE, 504, SB Touch, 563, 201, 204, 208, MPMAX 221, M80, Explorer, Explorer2.
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