Hello GPREV.1,We have tested the FW from our side and it works correctly. You can try to send packets of 128 bytes (multiple of 64 bytes) in loop mode:USBD_CDC_SetTxBuffer(&hUsbDeviceFS, (uint8_t*)&UserTxBufferFS[0], 128);USBD_CDC_TransmitPacket(&hUs...

Hello CZhan.8,We have tested the use case with our firmware on the STM32H743I-EVAL board using the latest version, v1.11.0, and everything is working properly.Please make sure that you are also using the latest version of the firmware, or if possible...