Jittering when flying acro on fpv

Anyone had similar experience. I tries to do some long range video flying in acro mode but found alot of small vibration at inteval of per half seconds.

But when i change to althold and poshold it seems all gone.

I suspect it has to do with slow bitrate from my elrs controller? It is causing unneeded movement.

Because I set my bitrate to the lowest to enable longest range. What do you think? Do you have similar problems before?