Dual reference monitors turning black every time I skip/scru

Hi there,
I am new to this so please forgive me but I recently purchased an HDMI splitter to send a signal out to two simultaneous reference monitors while I grade in Resolve. I am sending video signal through a Blackmagic Decklink 4K out to an OLED TV and an EIZO Coloredge. Whenever I skip/scrub through clips, both reference monitors turn black briefly, and then the image appears again in both. Both monitors go completely black during playback but I can see the image fine in the GUI on my central/third screen.

Here are all the details:
Mac Studio M1 Ultra computer
Thunderbolt to Sonnet chassis holding Decklink 4K
WARRKY HDMI splitter out from Decklink
1x HDMI out from splitter to EIZO Coloredge CG2420 HD monitor
1x HDMI out from splitter to Sony Bravia XR OLED UHD TV

Is the issue the splitter? Or the length of the HDMI cables? One monitor being HD and the other UHD? I was thinking I could send the HDMI to the EIZO and an SDI out to the TV but I don’t think the TV takes SDI. I don’t want to have to buy an SDI -> HDMI converter either.

Does anyone have any idea what I’m doing wrong here?

Well, HDMI is not really a professional standard, it was developed for home use. SDI is better.
It could be any of these: cable, splitter, or the devices not talking with each other.
Do the single monitors work well without the splitter? If so, I'd try another one and use high-quality cables as short as possible.

Hi Uli,

Thanks for your response and your advice. This is a home setup. I will look into a better splitter and higher quality HDMI cables. The monitors I own now do not have SDI inputs unfortunately.

Are you working interlaced or progressive? And what frame rate? Are both displays compatible with those settings? Is any component in the chain incompatible with those settings?

Are you working interlaced or progressive? And what frame rate? Are both displays compatible with those settings? Is any component in the chain incompatible with those settings?

I am working with progressive 23.976. Both displays are compatible with that, yes. I even have Blackmagic Desktop Video set to 4Kp23.98 DCI. HDMI splitter supports up to UHD 4K@30Hz. HDMI cables for the HD EIZO and UHD OLED are supported up to 4K@60Hz and 8K@60Hz respectively.