Have you tried being creative
The last tip spoke about being consistent in your marketing, now we're talking about being creative. Now this doesn't mean you have to be able to produce amazing videos or graphics for your channels, just try out the tools that the platforms are offering.
With twitter you're pretty stuck with posting videos and images, but you could also try polls and even venture in to Twitter ads and use twitter cards to post multiple images or videos with links etc
On Instagram you can upload videos and images, multiple images, landscape images in the form of multiple images, boomerang videos and stories too.
On Facebook you have a few more tools to play with, Facebook loves 360 images and video, you can play with different post types too. Carousel posts, product posts, polls, job openings etc
Have you tried all these types of posts? Why not give them a try next time you're posting to you page or profile and see if they have a better response from your audience.