External Monitors and displaylinksoftware, Netflix and Amazon Video no Video but Sound

You can't watch those services except on displays that support HDCP, and maybe not even then.

https://en.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection

I am pretty sure DisplayLink "fake" displays do not support HDCP.

I am also pretty sure DisplayLink displays are not suitable for full motion video -- great for spreadsheets, program listings, even stock quotes.

Hello Ndiii,

Try out the steps on this page: If your external display isn't detected or appears blurry when connected to your Mac - Apple Support under the section labeled "If your display is blank or not detected".

Try these steps if you don't see an image on your display.

Check your cable or adapter

Disconnect the cable from your external display from your Mac, then reconnect it. If the cable from your external display doesn't connect to the ports on your Mac, you can use a USB-C or Thunderbolt adapter. If you're using a USB-C or Thunderbolt adapter to connect a display, the adapter must be compliant with DisplayPort Alt Mode or Thunderbolt / USB 4.

Check how many displays you can connect

If you're connecting multiple displays to your Mac, use the Tech Specs page to find out how many external displays your Mac supports.

1. Choose Apple menu  > About This Mac, double-click your serial number, then press Command-C to copy it.

2. Go to the Tech Specs page, click the Search Tech Specs bar, press Command-V to enter your computer's serial number, then click Search.

3. Click the specs page for your Mac. The number of displays your Mac supports appears under Video Support or Graphics.

The information on this page may also help get this corrected: Use one or more external displays with your Mac - Apple Support.

Best wishes!