diff --git a/packages/frontend/src/components/MkMediaAudio.vue b/packages/frontend/src/components/MkMediaAudio.vue
index 75b31b9a4..53fd3b2d5 100644
--- a/packages/frontend/src/components/MkMediaAudio.vue
+++ b/packages/frontend/src/components/MkMediaAudio.vue
@@ -138,7 +138,7 @@ const rangePercent = computed({
 		audioEl.value.currentTime = to * durationMs.value / 1000;
 	},
 });
-const volume = ref(.5);
+const volume = ref(.25);
 const bufferedEnd = ref(0);
 const bufferedDataRatio = computed(() => {
 	if (!audioEl.value) return 0;
@@ -161,7 +161,7 @@ function togglePlayPause() {
 
 function toggleMute() {
 	if (volume.value === 0) {
-		volume.value = .5;
+		volume.value = .25;
 	} else {
 		volume.value = 0;
 	}
@@ -207,7 +207,7 @@ function init() {
 				isActuallyPlaying.value = false;
 				isPlaying.value = false;
 			});
-			
+
 			durationMs.value = audioEl.value.duration * 1000;
 			audioEl.value.addEventListener('durationchange', () => {
 				if (audioEl.value) {
diff --git a/packages/frontend/src/components/MkMediaRange.vue b/packages/frontend/src/components/MkMediaRange.vue
index e6303a5c4..a150ae984 100644
--- a/packages/frontend/src/components/MkMediaRange.vue
+++ b/packages/frontend/src/components/MkMediaRange.vue
@@ -5,9 +5,11 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 <!-- Media系専用のinput range -->
 <template>
-<div :class="$style.controlsSeekbar" :style="sliderBgWhite ? '--sliderBg: rgba(255,255,255,.25);' : '--sliderBg: var(--scrollbarHandle);'">
-	<progress v-if="buffer !== undefined" :class="$style.buffer" :value="isNaN(buffer) ? 0 : buffer" min="0" max="1">{{ Math.round(buffer * 100) }}% buffered</progress>
-	<input v-model="model" :class="$style.seek" :style="`--value: ${modelValue * 100}%;`" type="range" min="0" max="1" step="any" @change="emit('dragEnded', modelValue)"/>
+<div :style="sliderBgWhite ? '--sliderBg: rgba(255,255,255,.25);' : '--sliderBg: var(--scrollbarHandle);'">
+	<div :class="$style.controlsSeekbar">
+		<progress v-if="buffer !== undefined" :class="$style.buffer" :value="isNaN(buffer) ? 0 : buffer" min="0" max="1">{{ Math.round(buffer * 100) }}% buffered</progress>
+		<input v-model="model" :class="$style.seek" :style="`--value: ${modelValue * 100}%;`" type="range" min="0" max="1" step="any" @change="emit('dragEnded', modelValue)"/>
+	</div>
 </div>
 </template>
 
diff --git a/packages/frontend/src/components/MkMediaVideo.vue b/packages/frontend/src/components/MkMediaVideo.vue
index 977c9020c..0a113458a 100644
--- a/packages/frontend/src/components/MkMediaVideo.vue
+++ b/packages/frontend/src/components/MkMediaVideo.vue
@@ -176,7 +176,7 @@ const rangePercent = computed({
 		videoEl.value.currentTime = to * durationMs.value / 1000;
 	},
 });
-const volume = ref(.5);
+const volume = ref(.25);
 const bufferedEnd = ref(0);
 const bufferedDataRatio = computed(() => {
 	if (!videoEl.value) return 0;
@@ -236,7 +236,7 @@ function toggleFullscreen() {
 
 function toggleMute() {
 	if (volume.value === 0) {
-		volume.value = .5;
+		volume.value = .25;
 	} else {
 		volume.value = 0;
 	}
@@ -535,6 +535,9 @@ onDeactivated(() => {
 
 .seekbarRoot {
 	grid-area: seekbar;
+	/* ▼シークバー操作をやりやすくするためにクリックイベントが伝播されないエリアを拡張する */
+	margin: -10px;
+	padding: 10px;
 }
 
 @container (min-width: 500px) {
diff --git a/packages/frontend/src/filters/hms.ts b/packages/frontend/src/filters/hms.ts
index 7b5da965f..73db7becc 100644
--- a/packages/frontend/src/filters/hms.ts
+++ b/packages/frontend/src/filters/hms.ts
@@ -5,7 +5,7 @@
 
 import { i18n } from '@/i18n.js';
 
-export function hms(ms: number, options: {
+export function hms(ms: number, options?: {
 	textFormat?: 'colon' | 'locale';
 	enableSeconds?: boolean;
 	enableMs?: boolean;