has anyone ever had this problem?

i created an outgoing channel from expedition to have the targets displayed on the 20/20 B&G displays

i set alt 0 like this
upwind: bsp target
reaching: polar bps
downwind: bsp target
prestart: start timer

i set alt 1 like this
upwind: twa target
reaching: polar bps %
downwind: twa target
prestart: start timer

and finally i set alt 1 which alternates the alt 0 and 1 channels and send it as a custom channel on B&G websocket

i have this problem,
when i am on upwind or reaching, numbers displayed shift a lot. i mean i have a twa target of 38.8 and bsp targ 7.8, it show this number and suddently than 39 and 8

i have also this problem,
i wish have the tags of numbers but when it alternate the numbers does't alternate with tags but there are 1 sec late

can someone help me?
many thanks