Thanks a lot CKugl.1 . Your answer made my day :) I provide below my feedback on this matter, in case it can help any one out there in a similar situation: I come from the STM32F4 family and have been using CMSIS-DSP precompiled libraries for STM32F4...

Same issue here.Although in the HAL library (HAL_SD_InitCard function within stm32f4xx_hal_sd.c) initializes correctly toInit.BusWide = SDIO_BUS_WIDE_1B) you need to make sure that in your main.c file it is also corrected within the SDIO Init functio...