diff --git a/crates/tek_core/src/time.rs b/crates/tek_core/src/time.rs
index d7adb48f..f92730b8 100644
--- a/crates/tek_core/src/time.rs
+++ b/crates/tek_core/src/time.rs
@@ -266,16 +266,18 @@ impl UsecPosition<usize> for Instant {
     #[inline] fn usec (&self) -> usize { self.usec.load(Ordering::Relaxed) }
     #[inline] fn set_usec (&self, usec: usize) {
         self.usec.store(usec, Ordering::Relaxed);
-        self.set_sample(self.timebase.usecs_to_sample(usec as f64) as usize);
         self.set_pulse(self.timebase.usecs_to_pulse(usec as f64));
+        // FIXME: segfault!?!
+        //self.set_sample(self.timebase.usecs_to_sample(usec as f64) as usize);
     }
 }
 impl PulsePosition<f64> for Instant {
     #[inline] fn pulse (&self) -> f64 { self.pulse.load(Ordering::Relaxed) }
     #[inline] fn set_pulse (&self, pulse: f64) {
         self.pulse.store(pulse, Ordering::Relaxed);
-        self.set_sample(self.timebase.pulses_to_sample(pulse) as usize);
-        self.set_usec(self.timebase.pulses_to_usec(pulse) as usize);
+        // FIXME: segfault!?!
+        //self.set_usec(self.timebase.pulses_to_usec(pulse) as usize);
+        //self.set_sample(self.timebase.pulses_to_sample(pulse) as usize);
     }
 }
 impl PulsePosition<usize> for Instant {