diff --git a/frigate/storage.py b/frigate/storage.py
index 05e4fb42ab..e1875cac90 100644
--- a/frigate/storage.py
+++ b/frigate/storage.py
@@ -156,11 +156,13 @@ class StorageMaintainer(threading.Thread):
                     "bandwidth", 0
                 ),
                 # only streams with segments on disk are reported, so a camera
-                # keeps its sub entry until sub retention expires those segments
+                # keeps its sub entry until sub retention expires those segments.
+                # bandwidth is null rather than 0 when the cache holds no sample
+                # for the stream, since 0 would claim it writes nothing
                 "streams": {
                     stream_type: {
                         "usage": stream_usages[stream_type],
-                        "bandwidth": stream_bandwidths.get(stream_type, 0),
+                        "bandwidth": stream_bandwidths.get(stream_type),
                     }
                     for stream_type in (STREAM_TYPE_MAIN, STREAM_TYPE_SUB)
                     if stream_usages.get(stream_type)
diff --git a/frigate/test/test_storage.py b/frigate/test/test_storage.py
index 4f9e55f758..a5c5a84763 100644
--- a/frigate/test/test_storage.py
+++ b/frigate/test/test_storage.py
@@ -283,6 +283,49 @@ class TestHttp(unittest.TestCase):
             == MAX_CALCULATED_BANDWIDTH
         )
 
+    def test_stream_bandwidth_is_none_without_a_cached_sample(self):
+        """A stream that appears after the bandwidth cache freezes has no estimate.
+
+        Sub stream recording can be toggled on at runtime, so the cache can hold
+        a main-only sample while sub segments are already landing on disk.
+        Reporting 0 there would claim the sub stream costs nothing.
+        """
+        config = FrigateConfig(**self.minimal_config)
+        storage = StorageMaintainer(config, MagicMock())
+
+        time_keep = datetime.datetime.now().timestamp()
+        for i in range(60):
+            _insert_mock_recording(
+                f"main_{i}.frontdoor",
+                os.path.join(self.test_dir, f"main_{i}.tmp"),
+                time_keep + i * 10,
+                time_keep + i * 10 + 10,
+                seg_size=20,
+                seg_dur=10,
+            )
+
+        # 50 or more segments flips needs_refresh off, freezing the cache
+        storage.calculate_camera_bandwidth()
+        assert storage.camera_storage_stats["front_door"]["needs_refresh"] is False
+
+        for i in range(60):
+            _insert_mock_recording(
+                f"sub_{i}.frontdoor",
+                os.path.join(self.test_dir, f"sub_{i}.tmp"),
+                time_keep + 5000 + i * 10,
+                time_keep + 5000 + i * 10 + 10,
+                seg_size=2,
+                seg_dur=10,
+                stream_type=STREAM_TYPE_SUB,
+            )
+
+        storage.calculate_camera_bandwidth()
+        streams = storage.calculate_camera_usages()["front_door"]["streams"]
+
+        assert streams[STREAM_TYPE_SUB]["usage"] == 120
+        assert streams[STREAM_TYPE_SUB]["bandwidth"] is None
+        assert streams[STREAM_TYPE_MAIN]["bandwidth"] == 7200
+
     def test_camera_usages_with_no_recordings(self):
         """A camera with no segments reports zero usage and no streams."""
         config = FrigateConfig(**self.minimal_config)
diff --git a/web/src/components/graph/CombinedStorageGraph.tsx b/web/src/components/graph/CombinedStorageGraph.tsx
index c1ce711944..f909164aeb 100644
--- a/web/src/components/graph/CombinedStorageGraph.tsx
+++ b/web/src/components/graph/CombinedStorageGraph.tsx
@@ -204,9 +204,12 @@ export function CombinedStorageGraph({
 
   const getStreamSplit = useCallback(
     (row: StorageRow, field: keyof StreamStorage) => {
-      const sub = row.streams?.sub;
+      const mainValue = row.streams?.main?.[field];
+      const subValue = row.streams?.sub?.[field];
 
-      if (!sub) {
+      // omit the split entirely when either side is unknown, rather than
+      // showing a zero that would read as "this stream costs nothing"
+      if (mainValue == null || subValue == null) {
         return null;
       }
 
@@ -216,13 +219,13 @@ export function CombinedStorageGraph({
             <span className="text-muted-foreground">
               {t("quality.main", { ns: "components/player" })}
             </span>{" "}
-            {getUnitSize(row.streams?.main?.[field] ?? 0)}
+            {getUnitSize(mainValue)}
           </div>
           <div>
             <span className="text-muted-foreground">
               {t("quality.sub", { ns: "components/player" })}
             </span>{" "}
-            {getUnitSize(sub[field])}
+            {getUnitSize(subValue)}
           </div>
         </div>
       );
diff --git a/web/src/types/stats.ts b/web/src/types/stats.ts
index e824718e89..c9f3f0032a 100644
--- a/web/src/types/stats.ts
+++ b/web/src/types/stats.ts
@@ -103,7 +103,7 @@ export type StorageStats = {
 
 export type StreamStorage = {
   usage: number;
-  bandwidth: number;
+  bandwidth: number | null;
 };
 
 export type CameraStorage = {