diff --git a/sw/device/cheriot/soundstream/i2s.cc b/sw/device/cheriot/soundstream/i2s.cc
index 90a04bf..e5a5efb 100644
--- a/sw/device/cheriot/soundstream/i2s.cc
+++ b/sw/device/cheriot/soundstream/i2s.cc
@@ -54,7 +54,7 @@
   semaphore_put(&startup);
 }
 
-// NB: could be atomic but not needed for our ussage.
+// NB: could be atomic but not needed for our usage.
 volatile bool rx_watermark_seen = false;
 
 void i2s_isr(void) {
diff --git a/sw/device/cheriot/soundstream/mailbox.cc b/sw/device/cheriot/soundstream/mailbox.cc
index 174c17f..8861bbc 100644
--- a/sw/device/cheriot/soundstream/mailbox.cc
+++ b/sw/device/cheriot/soundstream/mailbox.cc
@@ -57,7 +57,7 @@
   semaphore_put(&startup);
 }
 
-// NB: could be atomic but not needed for our ussage.
+// NB: could be atomic but not needed for our usage.
 volatile bool button_pressed = false;
 
 void mailbox_isr(void) {
diff --git a/sw/device/cheriot/soundstream/ml_top.cc b/sw/device/cheriot/soundstream/ml_top.cc
index a7b04c8..38d51bf 100644
--- a/sw/device/cheriot/soundstream/ml_top.cc
+++ b/sw/device/cheriot/soundstream/ml_top.cc
@@ -60,7 +60,7 @@
   semaphore_put(&startup);
 }
 
-// NB: could be atomic but not needed for our ussage.
+// NB: could be atomic but not needed for our usage.
 volatile bool finish_done = false;
 
 void ml_top_isr(void) {