MC60 SPI problem

I use module MC60 with firmware MC60CAR01A13 and OpenCPU v 1.7.
In my case, I observe the SPI module is not working properly.

My program needs to read data from the flash and transfer it to a remote server through socket connection. A serious problem occurs when I transfer more than 256 bytes to a socket connection at a time. In this case, the SPI configured in the hardware mode falls and no read more data from flash.
If i configure SPI in simulation mode - еverything is working correctly. But in this mode the speed of reading on the SPI bus is slow and my program loses in performance.

Please help me deal with this problem.

Can I see your configuration code?