diff --git a/frontend/src/scenes/session-recordings/apm/playerInspector/ItemPerformanceEvent.tsx b/frontend/src/scenes/session-recordings/apm/playerInspector/ItemPerformanceEvent.tsx
index e195319f037f9..9b1d2f1a1e64f 100644
--- a/frontend/src/scenes/session-recordings/apm/playerInspector/ItemPerformanceEvent.tsx
+++ b/frontend/src/scenes/session-recordings/apm/playerInspector/ItemPerformanceEvent.tsx
@@ -65,7 +65,7 @@ export interface ItemPerformanceEvent {
     item: PerformanceEvent
     expanded: boolean
     setExpanded: (expanded: boolean) => void
-    finalTimestamp?: Dayjs
+    finalTimestamp: Dayjs | null
 }
 
 function renderTimeBenchmark(milliseconds: number): JSX.Element {
diff --git a/frontend/src/scenes/session-recordings/player/inspector/playerInspectorLogic.ts b/frontend/src/scenes/session-recordings/player/inspector/playerInspectorLogic.ts
index e83851eb58894..207491cbc0fe0 100644
--- a/frontend/src/scenes/session-recordings/player/inspector/playerInspectorLogic.ts
+++ b/frontend/src/scenes/session-recordings/player/inspector/playerInspectorLogic.ts
@@ -143,7 +143,7 @@ function snapshotDescription(snapshot: eventWithTime): string {
 
 function timeRelativeToStart(
     thingWithTime: eventWithTime | PerformanceEvent | RecordingConsoleLogV2 | RecordingEventType,
-    start: Dayjs | undefined
+    start: Dayjs | null
 ): {
     timeInRecording: number
     timestamp: dayjs.Dayjs
diff --git a/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.test.ts b/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.test.ts
index 8fbadb4fe773d..13279a313cf97 100644
--- a/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.test.ts
+++ b/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.test.ts
@@ -94,8 +94,8 @@ describe('sessionRecordingDataLogic', () => {
             expect(logic.values).toMatchObject({
                 bufferedToTime: null,
                 durationMs: 0,
-                start: undefined,
-                end: undefined,
+                start: null,
+                end: null,
                 segments: [],
                 sessionEventsData: null,
                 filters: {},
@@ -146,8 +146,8 @@ describe('sessionRecordingDataLogic', () => {
                 .toMatchValues({
                     sessionPlayerData: {
                         bufferedToTime: null,
-                        start: undefined,
-                        end: undefined,
+                        start: null,
+                        end: null,
                         durationMs: 0,
                         segments: [],
                         sessionRecordingId: '2',
diff --git a/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.ts b/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.ts
index ee412b93ea076..1db07b7544720 100644
--- a/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.ts
+++ b/frontend/src/scenes/session-recordings/player/sessionRecordingDataLogic.ts
@@ -245,7 +245,10 @@ async function processEncodedResponse(
 }
 
 const getSourceKey = (source: SessionRecordingSnapshotSource): string => {
-    return `${source.source}-${source.blob_key}`
+    // realtime sources vary so blob_key is not always present and is either null or undefined...
+    // we only care about key when not realtime
+    // and we'll always have a key when not realtime
+    return `${source.source}-${source.blob_key || source.source}`
 }
 
 export const sessionRecordingDataLogic = kea<sessionRecordingDataLogicType>([
@@ -751,29 +754,52 @@ export const sessionRecordingDataLogic = kea<sessionRecordingDataLogicType>([
             },
         ],
 
+        firstSnapshot: [
+            (s) => [s.snapshots],
+            (snapshots): RecordingSnapshot | null => {
+                return snapshots[0] || null
+            },
+        ],
+
+        lastSnapshot: [
+            (s) => [s.snapshots],
+            (snapshots): RecordingSnapshot | null => {
+                return snapshots[snapshots.length - 1] || null
+            },
+        ],
+
         start: [
-            (s) => [s.sessionPlayerMetaData],
-            (meta): Dayjs | undefined => {
-                return meta?.start_time ? dayjs(meta.start_time) : undefined
+            (s) => [s.firstSnapshot, s.sessionPlayerMetaData],
+            (firstSnapshot, meta): Dayjs | null => {
+                const eventStart = meta?.start_time ? dayjs(meta.start_time) : null
+                const snapshotStart = firstSnapshot ? dayjs(firstSnapshot.timestamp) : null
+
+                // whichever is earliest
+                if (eventStart && snapshotStart) {
+                    return eventStart.isBefore(snapshotStart) ? eventStart : snapshotStart
+                }
+                return eventStart || snapshotStart
             },
         ],
 
         end: [
-            (s) => [s.sessionPlayerMetaData, s.snapshots],
-            (meta, snapshots): Dayjs | undefined => {
-                // NOTE: We might end up with more snapshots than we knew about when we started the recording so we
-                // either use the metadata end point or the last snapshot, whichever is later.
-                const end = meta?.end_time ? dayjs(meta.end_time) : undefined
-                const lastEvent = snapshots?.slice(-1)[0]
-
-                return lastEvent?.timestamp && lastEvent.timestamp > +(end ?? 0) ? dayjs(lastEvent.timestamp) : end
+            (s) => [s.lastSnapshot, s.sessionPlayerMetaData],
+            (lastSnapshot, meta): Dayjs | null => {
+                const eventEnd = meta?.end_time ? dayjs(meta.end_time) : null
+                const snapshotEnd = lastSnapshot ? dayjs(lastSnapshot.timestamp) : null
+
+                // whichever is latest
+                if (eventEnd && snapshotEnd) {
+                    return eventEnd.isAfter(snapshotEnd) ? eventEnd : snapshotEnd
+                }
+                return eventEnd || snapshotEnd
             },
         ],
 
         durationMs: [
             (s) => [s.start, s.end],
             (start, end): number => {
-                return end?.diff(start) ?? 0
+                return !!start && !!end ? end.diff(start) : 0
             },
         ],
 
diff --git a/frontend/src/scenes/session-recordings/player/utils/segmenter.ts b/frontend/src/scenes/session-recordings/player/utils/segmenter.ts
index a8ffe60efb57e..456dc1e7ebd43 100644
--- a/frontend/src/scenes/session-recordings/player/utils/segmenter.ts
+++ b/frontend/src/scenes/session-recordings/player/utils/segmenter.ts
@@ -46,8 +46,8 @@ export const mapSnapshotsToWindowId = (snapshots: RecordingSnapshot[]): Record<s
 
 export const createSegments = (
     snapshots: RecordingSnapshot[],
-    start?: Dayjs,
-    end?: Dayjs,
+    start: Dayjs | null,
+    end: Dayjs | null,
     trackedWindow?: string | null
 ): RecordingSegment[] => {
     let segments: RecordingSegment[] = []
diff --git a/frontend/src/types.ts b/frontend/src/types.ts
index b0b40afa5ab2e..6409502958538 100644
--- a/frontend/src/types.ts
+++ b/frontend/src/types.ts
@@ -913,8 +913,8 @@ export interface SessionPlayerData {
     bufferedToTime: number | null
     snapshotsByWindowId: Record<string, eventWithTime[]>
     durationMs: number
-    start?: Dayjs
-    end?: Dayjs
+    start: Dayjs | null
+    end: Dayjs | null
     fullyLoaded: boolean
     sessionRecordingId: SessionRecordingId
 }