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Loss of signal behavior - differences between BM cards.

PostPosted: Fri Mar 26, 2021 6:42 pm
by Steven Toth
New users, quick question.

Imagine I have a kumo 12G SDI router with multiple 100% clean 720p59.94 feeds available for routing to any destination. Blackmagic cards are always the destination.

Multiple blackmagic based capture systems receiving these feeds:

* Servers running the original DUO cards with 10.1.1 see little or no frame loss if I switch inputs to the card via the router, maybe 2-3 frames of loss, the applications see little or no frame loss.

* Servers running DUO2s, QUAD2s, with various SDKS and firmwares from 10.8 to 12.0, we've tried a lot, all report significantly more frame loss when changing inputs on the kumo, as much as 200-700ms before the signal stabilizes.

* Windows PC, DUO2, 11.6 drivers running Media Express, rending the input to screen. Swithcing inputs seems to create roughly 3-500ms of lost video (not a clean switch).

Tried multiple kumos, multiple capture apps (VMIS, desktop video) (including SDK apps and apps derived from the sdks).

Tried full vs half duplex, no change. Tried, progressive vs interlaced content, roughly the same amount of loss occurs.

Cards from other vendors behave more like the DUO than the new DUO2/Quad2 etc.

DUO performing significanly better than the DUO2, Quad2. I don't think I've tried our 8K cards.

Replaced all the cabling multiple times, changed the feeds, changed the cards, changed the routers. Happening at multiples sites, this isn't a onetime thing.

Does this sound familiar to anyone?

I'd welcome your input.

- Steve