Are there settings for quality on mp4/mkv?

I have a casting app. On Android TV it can use Google Cast or an ExoPlayer receiver. On Fire TV it can use Amazon Fling or our ExoPlayer receiver.

I've had users report that Google Cast or Amazon Fling display better quality than our ExoPlayer receiver. Same TV, same streaming device, same mp4/mkv video.

Neither Google Cast nor Fling offer any kind o configuration for quality. Does ExoPlayer offer anything?

It isn't a huge difference but it does look like there is a difference.

ExoPlayer:

Amazon Fling:

Google Cast:

ExoPlayer:

Is there anything I can do to help with this? I'm using 2.17.1 without any extras like ffmpeg for example.

Thanks.