sending above 8 hz reboots arduino uno with readbearlab shield v1.1

Hi,

I'm using an arduino uno with a readbearlab shield with v1.1 to send sensor data to a android phone.
There is a libaray available : Releases · NordicSemiconductor/ble-sdk-arduino · GitHub
Using a timer interrupt I try to send data every 0.1 sec (10hz) to the phone.

This works for about 90 packets and then the arduino crashes (strange characters on serial monitor) and reboots

But at 8Hz it works fine...

Can anyone tell me why?

Thanks!

If found out that the arduino is running out of memory at frequencies above 8Hz.
When it runs out of sram memory it reboots...

Does anyone have an idea what is causing the increased memory usage at higher send frequencies?