diff --git a/drivers/sensor/tdk/icm45686/icm45686.h b/drivers/sensor/tdk/icm45686/icm45686.h
index f6a4918c36a13..6f5cd195c3f6e 100644
--- a/drivers/sensor/tdk/icm45686/icm45686.h
+++ b/drivers/sensor/tdk/icm45686/icm45686.h
@@ -82,7 +82,7 @@ struct icm45686_encoded_data {
 	struct icm45686_encoded_header header;
 	union {
 		struct icm45686_encoded_payload payload;
-		struct icm45686_encoded_fifo_payload fifo_payload;
+		FLEXIBLE_ARRAY_DECLARE(struct icm45686_encoded_fifo_payload, fifo_payload);
 	};
 };
 
diff --git a/drivers/sensor/tdk/icm45686/icm45686_decoder.c b/drivers/sensor/tdk/icm45686/icm45686_decoder.c
index 8326228a48764..52ae4a8198a06 100644
--- a/drivers/sensor/tdk/icm45686/icm45686_decoder.c
+++ b/drivers/sensor/tdk/icm45686/icm45686_decoder.c
@@ -7,6 +7,7 @@
  */
 
 #include <zephyr/drivers/sensor_clock.h>
+#include <zephyr/sys/check.h>
 
 #include "icm45686.h"
 #include "icm45686_reg.h"
@@ -475,7 +476,7 @@ static int icm45686_fifo_decode(const uint8_t *buffer,
 				void *data_out)
 {
 	struct icm45686_encoded_data *edata = (struct icm45686_encoded_data *)buffer;
-	struct icm45686_encoded_fifo_payload *frame_begin = &edata->fifo_payload;
+	struct icm45686_encoded_fifo_payload *frame_begin = edata->fifo_payload;
 	int count = 0;
 	int err;
 
@@ -489,11 +490,13 @@ static int icm45686_fifo_decode(const uint8_t *buffer,
 		/** This driver assumes 20-byte fifo packets, with both accel and gyro,
 		 * and no auxiliary sensors.
 		 */
-		__ASSERT(!(fdata->header & FIFO_HEADER_EXT_HEADER_EN(true)) &&
+		CHECKIF(!(!(fdata->header & FIFO_HEADER_EXT_HEADER_EN(true)) &&
 			(fdata->header & FIFO_HEADER_ACCEL_EN(true)) &&
 			(fdata->header & FIFO_HEADER_GYRO_EN(true)) &&
-			(fdata->header & FIFO_HEADER_HIRES_EN(true)),
-			"Unsupported FIFO packet format");
+			(fdata->header & FIFO_HEADER_HIRES_EN(true)))) {
+			LOG_ERR("Unsupported FIFO packet format 0x%02x", fdata->header);
+			return -ENOTSUP;
+		}
 
 		switch (chan_spec.chan_type) {
 		case SENSOR_CHAN_ACCEL_XYZ:
diff --git a/drivers/sensor/tdk/icm45686/icm45686_stream.c b/drivers/sensor/tdk/icm45686/icm45686_stream.c
index 0d6281433b15b..2741593b2523e 100644
--- a/drivers/sensor/tdk/icm45686/icm45686_stream.c
+++ b/drivers/sensor/tdk/icm45686/icm45686_stream.c
@@ -470,8 +470,16 @@ void icm45686_stream_submit(const struct device *dev,
 
 		if (data->stream.settings.enabled.fifo_ths ||
 		    data->stream.settings.enabled.fifo_full) {
+			/** AN-000364: When operating in FIFO streaming mode, if FIFO threshold
+			 * interrupt is triggered with M number of FIFO frames accumulated in the
+			 * FIFO buffer, the host should only read the first M-1 number of FIFO
+			 * frames.
+			 *
+			 * To avoid the case where M == 1 and M-- would be 0,
+			 * M + 1 threshold is used so M count is read.
+			 */
 			uint16_t fifo_ths = data->stream.settings.enabled.fifo_ths ?
-					    cfg->settings.fifo_watermark : 0;
+					    cfg->settings.fifo_watermark + 1 : 0;
 
 			val = REG_FIFO_CONFIG2_FIFO_WM_GT_THS(true) |
 			      REG_FIFO_CONFIG2_FIFO_FLUSH(true);