diff --git a/boards/arm/cxd56xx/spresense/configs/fmsynth/defconfig b/boards/arm/cxd56xx/spresense/configs/fmsynth/defconfig
new file mode 100644
index 0000000000..ca717fb3c6
--- /dev/null
+++ b/boards/arm/cxd56xx/spresense/configs/fmsynth/defconfig
@@ -0,0 +1,91 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_AUDIO_FORMAT_MP3 is not set
+# CONFIG_AUDIO_FORMAT_PCM is not set
+# CONFIG_CXD56_I2C0_SCUSEQ is not set
+# CONFIG_MMCSD_HAVE_WRITEPROTECT is not set
+# CONFIG_MMCSD_SPI is not set
+# CONFIG_MTD_SMART_WEAR_LEVEL is not set
+# CONFIG_STANDARD_SERIAL is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="spresense"
+CONFIG_ARCH_BOARD_COMMON=y
+CONFIG_ARCH_BOARD_SPRESENSE=y
+CONFIG_ARCH_CHIP="cxd56xx"
+CONFIG_ARCH_CHIP_CXD56XX=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARMV7M_USEBASEPRI=y
+CONFIG_AUDIO=y
+CONFIG_AUDIOUTILS_FMSYNTH_LIB=y
+CONFIG_AUDIOUTILS_MMLPARSER_LIB=y
+CONFIG_AUDIOUTILS_NXAUDIO_LIB=y
+CONFIG_AUDIO_CXD56=y
+CONFIG_BOARD_LOOPSPERMSEC=5434
+CONFIG_BOOT_RUNFROMISRAM=y
+CONFIG_BUILTIN=y
+CONFIG_CXD56_BINARY=y
+CONFIG_CXD56_I2C0=y
+CONFIG_CXD56_I2C=y
+CONFIG_CXD56_SDIO=y
+CONFIG_CXD56_SPI4=y
+CONFIG_CXD56_SPI5=y
+CONFIG_CXD56_SPI=y
+CONFIG_CXD56_USBDEV=y
+CONFIG_DEBUG_FULLOPT=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DRIVERS_AUDIO=y
+CONFIG_EXAMPLES_FMSYNTH=y
+CONFIG_FAT_LCNAMES=y
+CONFIG_FAT_LFN=y
+CONFIG_FS_FAT=y
+CONFIG_FS_PROCFS=y
+CONFIG_FS_PROCFS_REGISTER=y
+CONFIG_FS_SMARTFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_INIT_ENTRYPOINT="spresense_main"
+CONFIG_MMCSD=y
+CONFIG_MMCSD_SDIO=y
+CONFIG_MTD_BYTE_WRITE=y
+CONFIG_MTD_PARTITION=y
+CONFIG_MTD_SMART=y
+CONFIG_MTD_SMART_ENABLE_CRC=y
+CONFIG_MTD_SMART_SECTOR_SIZE=4096
+CONFIG_NAME_MAX=128
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_READLINE=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=1572864
+CONFIG_RAM_START=0x0d000000
+CONFIG_READLINE_CMD_HISTORY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_RTC=y
+CONFIG_RTC_DRIVER=y
+CONFIG_SCHED_HPWORK=y
+CONFIG_SCHED_LPWORK=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_SMARTFS_ALIGNED_ACCESS=y
+CONFIG_SMARTFS_MAXNAMLEN=30
+CONFIG_SMARTFS_MULTI_ROOT_DIRS=y
+CONFIG_SPECIFIC_DRIVERS=y
+CONFIG_SPI=y
+CONFIG_SPRESENSE_EXTENSION=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_SYSTEM_CLE=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_SYSTEM_USBMSC=y
+CONFIG_UART1_SERIAL_CONSOLE=y
+CONFIG_USBDEV=y
+CONFIG_USBDEV_DMA=y
+CONFIG_USBDEV_DUALSPEED=y
+CONFIG_USBMSC=y
+CONFIG_USBMSC_EPBULKIN=1
+CONFIG_USBMSC_REMOVABLE=y