diff --git a/common/clients/mix-client/src/poisson.rs b/common/clients/mix-client/src/poisson.rs
index 6474d3c65b..e4bc83de7a 100644
--- a/common/clients/mix-client/src/poisson.rs
+++ b/common/clients/mix-client/src/poisson.rs
@@ -1,9 +1,10 @@
 use rand_distr::{Distribution, Exp};
+use std::time;
 
-pub fn sample(average_delay: f64) -> f64 {
+pub fn sample_from_duration(average_duration: time::Duration) -> time::Duration {
     // this is our internal code used by our traffic streams
     // the error is only thrown if average delay is less than 0, which will never happen
     // so call to unwrap is perfectly safe here
-    let exp = Exp::new(1.0 / average_delay).unwrap();
-    exp.sample(&mut rand::thread_rng())
+    let exp = Exp::new(1.0 / average_duration.as_nanos() as f64).unwrap();
+    time::Duration::from_nanos(exp.sample(&mut rand::thread_rng()).round() as u64)
 }