Problem with Serial send/receive with Simulink

Hello everyone,
this is my first time on these forums, so i appreciate any help.
I am trying to send and receive data between my mRo pixhawk 1 and Simulink, however im running into issues.

Model that is flashed onto the pixhawk:

Model that is running in Simulink desktop-real-Time:

as you can see, the message is sent at 100 Hz.
When i set the packet-input block to more than, or exactly 100Hz, i get jiberish:

when i set packet input block to less than 100Hz, i get data that is “slow”
for example at 10Hz i get this: Note that the frequency of the sine wave here is about 10x slower than it should be.

I believe this has something to do with “serial caching” but i have no idea how to get around it
Thanks for the help!!