in a job today, using 5.9.1, got a lot of drop frames along audio buzz, in the BM SDI outputs and to a lesser extent, to youtube stream.
Set up
2019 16" MBP, i7, 16 gb ram, radeon 5300 4gb
Document set at 720P 59.94
USB 3.0 hdmi generic capture - no audio (zoom 15" rMBP )
Decklink duo 2 TB2
Ch1: camera input 720P 59.94
Ch2: none
Ch3: program output to Hyperdeck SSD recorder 720P 59.94
Ch4: usb computer capture direct output - no audio 1080p 30 (to TV)
2 lower third
1 station logo
Audio
Soundcraft notepad 12FX - USB (trough Loopback to avoid audio “clicks”)
Streaming to youtube - program output - 2500 mbps
Virtual camera to zoom
If you are on the 16" MBP, please make sure that you have the Turbo Boost Mode Switcher (http://tbswitcher.rugarciap.com/) installed and turned of the Turbo Boost Mode to make sure that you do not get thermal issues.
Did the frames drop in the output or on the input side? What macOS are you using and what version of the Blackmagic Desktop Video Software?
Yes. If Turbo Boost is on, the processor will srart to oscillate between short bursts of super high performance followed by ever bigger slowdowns to cool off. If you turn it off, performance will be slightly less but constant.