diff --git a/src/platforms/posix/px4_layer/drv_hrt.c b/src/platforms/posix/px4_layer/drv_hrt.c
index 0544131705..3b0502866c 100644
--- a/src/platforms/posix/px4_layer/drv_hrt.c
+++ b/src/platforms/posix/px4_layer/drv_hrt.c
@@ -81,35 +81,23 @@ static void hrt_unlock(void)
 	px4_sem_post(&_hrt_lock);
 }
 
-#ifdef __PX4_DARWIN
-
-#include <mach/mach_time.h>
-#define MAC_NANO (+1.0E-9)
-#define MAC_GIGA UINT64_C(1000000000)
-#define CLOCK_MONOTONIC 1
-#define HRT_LOCK_NAME "/hrt_lock"
-
-static double px4_timebase = 0.0;
+#if defined(__APPLE__) && defined(__MACH__)
+#include <time.h>
+#include <sys/time.h>
+#define CLOCK_REALTIME 0
 
 int px4_clock_gettime(clockid_t clk_id, struct timespec *tp)
 {
-	if (clk_id != CLOCK_MONOTONIC) {
-		return 1;
+	struct timeval now;
+	int rv = gettimeofday(&now, NULL);
+
+	if(rv) {
+		return rv;
 	}
 
-	if (!px4_timestart) {
-		mach_timebase_info_data_t tb = {};
-		mach_timebase_info(&tb);
-		px4_timebase = tb.numer;
-		px4_timebase /= tb.denom;
-		// px4_timestart = mach_absolute_time();
-	}
+	tp->tv_sec = now.tv_sec;
+	tp->tv_nsec = now.tv_usec * 1000;
 
-	memset(tp, 0, sizeof(*tp));
-
-	double diff = mach_absolute_time() * px4_timebase;
-	tp->tv_sec = diff * MAC_NANO;
-	tp->tv_nsec = diff - (tp->tv_sec * MAC_GIGA);
 	return 0;
 }