diff --git a/internal/api/v20240610preview/conversion_fuzz_test.go b/internal/api/v20240610preview/conversion_fuzz_test.go
index 764c711a42..8575f4b89d 100644
--- a/internal/api/v20240610preview/conversion_fuzz_test.go
+++ b/internal/api/v20240610preview/conversion_fuzz_test.go
@@ -66,6 +66,14 @@ func TestRoundTripInternalExternalInternal(t *testing.T) {
 			// ClusterServiceID does not roundtrip through the external type because it is purely an internal detail
 			j.ClusterServiceID = ocm.InternalID{}
 		},
+		func(j *api.CustomerManagedEncryptionProfile, c randfill.Continue) {
+			c.FillNoCustom(j)
+			// we cannot properly roundtrip a zero value here, so nil when that happens
+			zeroValueKMS := api.KmsEncryptionProfile{}
+			if j.Kms != nil && *j.Kms == zeroValueKMS {
+				j.Kms = nil
+			}
+		},
 	}, rand.NewSource(seed))
 
 	// Try a few times, since runTest uses random values.
diff --git a/internal/api/v20251223preview/conversion_fuzz_test.go b/internal/api/v20251223preview/conversion_fuzz_test.go
index bedd2cbacf..b5ef7a88c9 100644
--- a/internal/api/v20251223preview/conversion_fuzz_test.go
+++ b/internal/api/v20251223preview/conversion_fuzz_test.go
@@ -66,6 +66,14 @@ func TestRoundTripInternalExternalInternal(t *testing.T) {
 			// ClusterServiceID does not roundtrip through the external type because it is purely an internal detail
 			j.ClusterServiceID = ocm.InternalID{}
 		},
+		func(j *api.CustomerManagedEncryptionProfile, c randfill.Continue) {
+			c.FillNoCustom(j)
+			// we cannot properly roundtrip a zero value here, so nil when that happens
+			zeroValueKMS := api.KmsEncryptionProfile{}
+			if j.Kms != nil && *j.Kms == zeroValueKMS {
+				j.Kms = nil
+			}
+		},
 	}, rand.NewSource(seed))
 
 	// Try a few times, since runTest uses random values.