diff --git a/code/espurna/types.cpp b/code/espurna/types.cpp
index b8dea724..3b559e93 100644
--- a/code/espurna/types.cpp
+++ b/code/espurna/types.cpp
@@ -383,6 +383,10 @@ update_floating:
 
 update_decimal:
     {
+        if ((last != Type::Unknown) && (type == Type::Unknown)) {
+            goto reset;
+        }
+
         const auto result = parseUnsigned(token, 10);
         if (result.ok) {
             // num and den are constexpr and bound to ratio types, so duration cast has to happen manually
diff --git a/code/test/unit/src/settings/settings.cpp b/code/test/unit/src/settings/settings.cpp
index 95b00910..eb94b837 100644
--- a/code/test/unit/src/settings/settings.cpp
+++ b/code/test/unit/src/settings/settings.cpp
@@ -221,6 +221,11 @@ void test_parse_duration_spec() {
 }
 
 void test_parse_fail_duration_spec() {
+    test_parse_fail("1000us100");
+    test_parse_fail("100s50");
+    test_parse_fail("ms100");
+    test_parse_fail("s200");
+    test_parse_fail("u300");
     test_parse_fail("123ui");
     test_parse_fail("123s456sm");
     test_parse_fail("456s\x01\\789uu");