W5100S packet reading error in // mode

We are designing a product with a W5100s in // mode. We have wired a WIZ810SMJ board on our actual product board.
We have some error in the received packet. we sometime receive some packet with some eroneous data.

To verify if the issue come from our implementation or not we make some test with the W5100S-EVB.
with this board we were reproduce the issue. sometime we have wrong data in the packet received.

Do you have some know issue in using the // mode on the W5100S?

some share on our investigation.

The error seems to apend when the RX buffer roll out in the wiz_recv_data function

size = getSn_RxMAX(sn) - src_mask;
WIZCHIP_READ_BUF((uint32_t)src_ptr, (uint8_t*)wizdata, size);
wizdata += size;
size = len - size;
src_ptr = getSn_RxBASE(sn);
WIZCHIP_READ_BUF(src_ptr, (uint8_t*)wizdata, size);


Error append when we make the read of the buffer in two step.

If it can help having the root cause.