Switches, adapters and dongles on HDMI connections are very prone to display issues. If the issue is not occurring with a direct connection from the laptop to the display then the switch is suspect. One thing you can do is be sure you are using high quality HDMI cables. Here is a table on HDMI cable types from the Wiki on HDMI.
- Standard HDMI Cable – up to 1080i and 720p
- Standard HDMI Cable with Ethernet
- High Speed HDMI Cable – 1080p, 4K, 3D and deep color
- High Speed HDMI Cable with Ethernet