I'm in need of some advice with a video installation build I'm currently working on.
I recently bought 3x Sony PVM-20L2MD and 1x SonyPVM-20M2MDE monitors as seen below:

This whole project is very much out of my comfort zone, the seller I bought the monitors off strongly recommended I use this forum for advice to help with my build.
The monitors are to be used as shown, stacked 2 x 2 to form a video installation.
I require each monitor to play both individual videos on loop from separate media players and also the ability to daisy chain the monitors to play a single video across all 4 monitors.
I have been experimenting with how to make this setup work.
So far I have managed to get video to play from my 2017 Macbook Pro:



I am waiting on some s-video to s-video cables to test a daisy chain setup.
The whole setup is far from ideal, the picture is not optimal and is somewhat unstable as it often reverts to the colour bar screen if any of the rca connections are disturbed:

The setup I am using is a HDMI to Composite AV Converter and a RF Modulator to convert the HDMI signal:


The media players I intend to use for the build are the Brightsign LS424, below:

https://www.brightsign.biz/digital-sign ... Line/LS424
I would really appreciate any advice on how I can make a better/more stable setup to achieve what I need.
Kind Regards,
James