diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ccdd91007..8a2613ef8d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -39,6 +39,7 @@
 
 ### Client
 - Enhance: 二要素認証のバックアップコード一覧をテキストファイルでダウンロード可能に
+- Enhance: 動画再生時のデフォルトボリュームを30%に
 - Fix: リアクションしたユーザ一覧のUIが稀に左上に残ってしまう不具合を修正
 
 ### Server
diff --git a/packages/backend/src/server/api/endpoints/notes/hybrid-timeline.ts b/packages/backend/src/server/api/endpoints/notes/hybrid-timeline.ts
index 33ffd42a76..d5b706e543 100644
--- a/packages/backend/src/server/api/endpoints/notes/hybrid-timeline.ts
+++ b/packages/backend/src/server/api/endpoints/notes/hybrid-timeline.ts
@@ -93,20 +93,23 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 
 			const limit = ps.limit + (ps.untilId ? 1 : 0) + (ps.sinceId ? 1 : 0); // untilIdに指定したものも含まれるため+1
 
-			const [htlNoteIds, ltlNoteIds] = await Promise.all([
-				this.redisForTimelines.xrevrange(
-					ps.withFiles ? `homeTimelineWithFiles:${me.id}` : `homeTimeline:${me.id}`,
-					ps.untilId ? this.idService.parse(ps.untilId).date.getTime() : ps.untilDate ?? '+',
-					ps.sinceId ? this.idService.parse(ps.sinceId).date.getTime() : ps.sinceDate ?? '-',
-					'COUNT', limit,
-				).then(res => res.map(x => x[1][1]).filter(x => x !== ps.untilId && x !== ps.sinceId)),
-				this.redisForTimelines.xrevrange(
-					ps.withFiles ? 'localTimelineWithFiles' : 'localTimeline',
-					ps.untilId ? this.idService.parse(ps.untilId).date.getTime() : ps.untilDate ?? '+',
-					ps.sinceId ? this.idService.parse(ps.sinceId).date.getTime() : ps.sinceDate ?? '-',
-					'COUNT', limit,
-				).then(res => res.map(x => x[1][1]).filter(x => x !== ps.untilId && x !== ps.sinceId)),
-			]);
+			const redisPipeline = this.redisForTimelines.pipeline();
+			redisPipeline.xrevrange(
+				ps.withFiles ? `homeTimelineWithFiles:${me.id}` : `homeTimeline:${me.id}`,
+				ps.untilId ? this.idService.parse(ps.untilId).date.getTime() : ps.untilDate ?? '+',
+				ps.sinceId ? this.idService.parse(ps.sinceId).date.getTime() : ps.sinceDate ?? '-',
+				'COUNT', limit,
+			);
+			redisPipeline.xrevrange(
+				ps.withFiles ? 'localTimelineWithFiles' : 'localTimeline',
+				ps.untilId ? this.idService.parse(ps.untilId).date.getTime() : ps.untilDate ?? '+',
+				ps.sinceId ? this.idService.parse(ps.sinceId).date.getTime() : ps.sinceDate ?? '-',
+				'COUNT', limit,
+			);
+			const [htlNoteIds, ltlNoteIds] = await redisPipeline.exec().then(res => res ? [
+				(res[0][1] as string[][]).map(x => x[1][1]).filter(x => x !== ps.untilId && x !== ps.sinceId),
+				(res[1][1] as string[][]).map(x => x[1][1]).filter(x => x !== ps.untilId && x !== ps.sinceId),
+			] : []);
 
 			let noteIds = Array.from(new Set([...htlNoteIds, ...ltlNoteIds]));
 			noteIds.sort((a, b) => a > b ? -1 : 1);
diff --git a/packages/frontend/src/components/MkMediaBanner.vue b/packages/frontend/src/components/MkMediaBanner.vue
index 10b2ac9ece..69da1a7466 100644
--- a/packages/frontend/src/components/MkMediaBanner.vue
+++ b/packages/frontend/src/components/MkMediaBanner.vue
@@ -17,7 +17,6 @@ SPDX-License-Identifier: AGPL-3.0-only
 			:title="media.name"
 			controls
 			preload="metadata"
-			@volumechange="volumechange"
 		/>
 	</div>
 	<a
@@ -33,7 +32,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 </template>
 
 <script lang="ts" setup>
-import { onMounted } from 'vue';
+import { onMounted, shallowRef, watch } from 'vue';
 import * as Misskey from 'misskey-js';
 import { soundConfigStore } from '@/scripts/sound.js';
 import { i18n } from '@/i18n.js';
@@ -43,15 +42,13 @@ const props = withDefaults(defineProps<{
 }>(), {
 });
 
-const audioEl = $shallowRef<HTMLAudioElement | null>();
+const audioEl = shallowRef<HTMLAudioElement>();
 let hide = $ref(true);
 
-function volumechange() {
-	if (audioEl) soundConfigStore.set('mediaVolume', audioEl.volume);
-}
-
-onMounted(() => {
-	if (audioEl) audioEl.volume = soundConfigStore.state.mediaVolume;
+watch(audioEl, () => {
+	if (audioEl.value) {
+		audioEl.value.volume = 0.3;
+	}
 });
 </script>
 
diff --git a/packages/frontend/src/components/MkMediaVideo.vue b/packages/frontend/src/components/MkMediaVideo.vue
index 751b5f7570..43c64b4c85 100644
--- a/packages/frontend/src/components/MkMediaVideo.vue
+++ b/packages/frontend/src/components/MkMediaVideo.vue
@@ -14,6 +14,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 </div>
 <div v-else :class="[$style.visible, (video.isSensitive && defaultStore.state.highlightSensitiveMedia) && $style.sensitiveContainer]">
 	<video
+		ref="videoEl"
 		:class="$style.video"
 		:poster="video.thumbnailUrl"
 		:title="video.comment"
@@ -31,7 +32,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 </template>
 
 <script lang="ts" setup>
-import { ref } from 'vue';
+import { ref, shallowRef, watch } from 'vue';
 import * as Misskey from 'misskey-js';
 import bytes from '@/filters/bytes.js';
 import { defaultStore } from '@/store.js';
@@ -42,6 +43,14 @@ const props = defineProps<{
 }>();
 
 const hide = ref((defaultStore.state.nsfw === 'force' || defaultStore.state.enableDataSaverMode) ? true : (props.video.isSensitive && defaultStore.state.nsfw !== 'ignore'));
+
+const videoEl = shallowRef<HTMLVideoElement>();
+
+watch(videoEl, () => {
+	if (videoEl.value) {
+		videoEl.value.volume = 0.3;
+	}
+});
 </script>
 
 <style lang="scss" module>
diff --git a/packages/frontend/src/scripts/sound.ts b/packages/frontend/src/scripts/sound.ts
index c7b5328618..1ef075818f 100644
--- a/packages/frontend/src/scripts/sound.ts
+++ b/packages/frontend/src/scripts/sound.ts
@@ -7,10 +7,6 @@ import { markRaw } from 'vue';
 import { Storage } from '@/pizzax.js';
 
 export const soundConfigStore = markRaw(new Storage('sound', {
-	mediaVolume: {
-		where: 'device',
-		default: 0.5,
-	},
 	sound_masterVolume: {
 		where: 'device',
 		default: 0.3,