My download and upload lately is fickle, I can't get rates locked in 15MiB / s, they always fluctuate a lot.

Is it some configuration I need to do in the tixati?

I sow 500 torrents on a private tracker and would like constant speeds.

(Google Translate)

Print:https://imgur.com/xqTCGZ4.png

anyone help me?

Fluctuation is completely normal with Bittorrent. If there's demand then you will upload more, if other seeds don't have fast internet connections too then they can give you enough speed to download.

Since you can't tell whether its the swarm speed issue (all other users in the network), it's safe to say that Tixati is operating normally.