diff --git a/src/components/ha-conversation-agent-picker.ts b/src/components/ha-conversation-agent-picker.ts
index 5175e99f35..b87f75f151 100644
--- a/src/components/ha-conversation-agent-picker.ts
+++ b/src/components/ha-conversation-agent-picker.ts
@@ -15,7 +15,7 @@ import "./ha-list-item";
 import "./ha-select";
 import type { HaSelect } from "./ha-select";
 
-const DEFAULT = "default_agent_option";
+const NONE = "__NONE_OPTION__";
 @customElement("ha-conversation-agent-picker")
 export class HaConversationAgentPicker extends LitElement {
   @property() public value?: string;
@@ -36,7 +36,7 @@ export class HaConversationAgentPicker extends LitElement {
     if (!this._agents) {
       return nothing;
     }
-    const value = this.value ?? DEFAULT;
+    const value = this.value ?? (this.required ? this._defaultAgent : NONE);
     return html`
       <ha-select
         .label=${this.label ||
@@ -51,16 +51,13 @@ export class HaConversationAgentPicker extends LitElement {
         fixedMenuPosition
         naturalMenuWidth
       >
-        <ha-list-item .value=${DEFAULT}>
-          ${this.hass!.localize(
-            "ui.components.coversation-agent-picker.default",
-            {
-              default: this._agents.find(
-                (agent) => agent.id === this._defaultAgent
-              )?.name,
-            }
-          )}
-        </ha-list-item>
+        ${!this.required
+          ? html`<ha-list-item .value=${NONE}>
+              ${this.hass!.localize(
+                "ui.components.coversation-agent-picker.none"
+              )}
+            </ha-list-item>`
+          : nothing}
         ${this._agents.map(
           (agent) =>
             html`<ha-list-item .value=${agent.id}>${agent.name}</ha-list-item>`
@@ -93,11 +90,11 @@ export class HaConversationAgentPicker extends LitElement {
       !this.hass ||
       target.value === "" ||
       target.value === this.value ||
-      (this.value === undefined && target.value === DEFAULT)
+      (this.value === undefined && target.value === NONE)
     ) {
       return;
     }
-    this.value = target.value === DEFAULT ? undefined : target.value;
+    this.value = target.value === NONE ? undefined : target.value;
     fireEvent(this, "value-changed", { value: this.value });
   }
 }
diff --git a/src/components/ha-stt-picker.ts b/src/components/ha-stt-picker.ts
index bbaab72be4..b7e998fb92 100644
--- a/src/components/ha-stt-picker.ts
+++ b/src/components/ha-stt-picker.ts
@@ -3,20 +3,22 @@ import {
   CSSResultGroup,
   html,
   LitElement,
-  PropertyValueMap,
+  nothing,
+  PropertyValues,
   TemplateResult,
 } from "lit";
 import { customElement, property, state } from "lit/decorators";
 import { fireEvent } from "../common/dom/fire_event";
 import { stopPropagation } from "../common/dom/stop_propagation";
 import { computeStateName } from "../common/entity/compute_state_name";
+import { debounce } from "../common/util/debounce";
 import { listSTTEngines, STTEngine } from "../data/stt";
 import { HomeAssistant } from "../types";
 import "./ha-list-item";
 import "./ha-select";
 import type { HaSelect } from "./ha-select";
 
-const DEFAULT = "default_engine_option";
+const NONE = "__NONE_OPTION__";
 
 @customElement("ha-stt-picker")
 export class HaSTTPicker extends LitElement {
@@ -35,7 +37,11 @@ export class HaSTTPicker extends LitElement {
   @state() _engines: STTEngine[] = [];
 
   protected render(): TemplateResult {
-    const value = this.value ?? DEFAULT;
+    const value =
+      this.value ??
+      (this.required
+        ? this._engines.find((engine) => engine.language_supported)
+        : NONE);
     return html`
       <ha-select
         .label=${this.label ||
@@ -48,9 +54,11 @@ export class HaSTTPicker extends LitElement {
         fixedMenuPosition
         naturalMenuWidth
       >
-        <ha-list-item .value=${DEFAULT}>
-          ${this.hass!.localize("ui.components.stt-picker.default")}
-        </ha-list-item>
+        ${!this.required
+          ? html`<ha-list-item .value=${NONE}>
+              ${this.hass!.localize("ui.components.stt-picker.none")}
+            </ha-list-item>`
+          : nothing}
         ${this._engines.map((engine) => {
           const stateObj = this.hass!.states[engine.engine_id];
           return html`<ha-list-item
@@ -64,14 +72,27 @@ export class HaSTTPicker extends LitElement {
     `;
   }
 
-  protected willUpdate(
-    changedProperties: PropertyValueMap<any> | Map<PropertyKey, unknown>
-  ): void {
+  protected willUpdate(changedProperties: PropertyValues<this>): void {
     super.willUpdate(changedProperties);
-    if (!this.hasUpdated || changedProperties.has("language")) {
-      listSTTEngines(this.hass, this.language).then((engines) => {
-        this._engines = engines.providers;
-      });
+    if (!this.hasUpdated) {
+      this._updateEngines();
+    } else if (changedProperties.has("language")) {
+      this._debouncedUpdateEngines();
+    }
+  }
+
+  private _debouncedUpdateEngines = debounce(() => this._updateEngines(), 500);
+
+  private async _updateEngines() {
+    this._engines = (await listSTTEngines(this.hass, this.language)).providers;
+
+    if (
+      this.value &&
+      !this._engines.find((engine) => engine.engine_id === this.value)
+        ?.language_supported
+    ) {
+      this.value = undefined;
+      fireEvent(this, "value-changed", { value: this.value });
     }
   }
 
@@ -89,11 +110,11 @@ export class HaSTTPicker extends LitElement {
       !this.hass ||
       target.value === "" ||
       target.value === this.value ||
-      (this.value === undefined && target.value === DEFAULT)
+      (this.value === undefined && target.value === NONE)
     ) {
       return;
     }
-    this.value = target.value === DEFAULT ? undefined : target.value;
+    this.value = target.value === NONE ? undefined : target.value;
     fireEvent(this, "value-changed", { value: this.value });
   }
 }
diff --git a/src/components/ha-tts-picker.ts b/src/components/ha-tts-picker.ts
index c0d5916a4d..fe671b3bea 100644
--- a/src/components/ha-tts-picker.ts
+++ b/src/components/ha-tts-picker.ts
@@ -1,22 +1,24 @@
+import { debounce } from "chart.js/helpers";
 import {
   css,
   CSSResultGroup,
   html,
   LitElement,
-  PropertyValueMap,
+  nothing,
+  PropertyValues,
   TemplateResult,
 } from "lit";
 import { customElement, property, state } from "lit/decorators";
 import { fireEvent } from "../common/dom/fire_event";
 import { stopPropagation } from "../common/dom/stop_propagation";
 import { computeStateName } from "../common/entity/compute_state_name";
-import { TTSEngine, listTTSEngines } from "../data/tts";
+import { listTTSEngines, TTSEngine } from "../data/tts";
 import { HomeAssistant } from "../types";
-import "./ha-select";
 import "./ha-list-item";
+import "./ha-select";
 import type { HaSelect } from "./ha-select";
 
-const DEFAULT = "default_engine_option";
+const NONE = "__NONE_OPTION__";
 
 @customElement("ha-tts-picker")
 export class HaTTSPicker extends LitElement {
@@ -35,7 +37,11 @@ export class HaTTSPicker extends LitElement {
   @state() _engines: TTSEngine[] = [];
 
   protected render(): TemplateResult {
-    const value = this.value ?? DEFAULT;
+    const value =
+      this.value ??
+      (this.required
+        ? this._engines.find((engine) => engine.language_supported)
+        : NONE);
     return html`
       <ha-select
         .label=${this.label ||
@@ -48,9 +54,11 @@ export class HaTTSPicker extends LitElement {
         fixedMenuPosition
         naturalMenuWidth
       >
-        <ha-list-item .value=${DEFAULT}>
-          ${this.hass!.localize("ui.components.tts-picker.default")}
-        </ha-list-item>
+        ${!this.required
+          ? html`<ha-list-item .value=${NONE}>
+              ${this.hass!.localize("ui.components.tts-picker.none")}
+            </ha-list-item>`
+          : nothing}
         ${this._engines.map((engine) => {
           const stateObj = this.hass!.states[engine.engine_id];
           return html`<ha-list-item
@@ -64,14 +72,27 @@ export class HaTTSPicker extends LitElement {
     `;
   }
 
-  protected willUpdate(
-    changedProperties: PropertyValueMap<any> | Map<PropertyKey, unknown>
-  ): void {
+  protected willUpdate(changedProperties: PropertyValues<this>): void {
     super.willUpdate(changedProperties);
-    if (!this.hasUpdated || changedProperties.has("language")) {
-      listTTSEngines(this.hass, this.language).then((engines) => {
-        this._engines = engines.providers;
-      });
+    if (!this.hasUpdated) {
+      this._updateEngines();
+    } else if (changedProperties.has("language")) {
+      this._debouncedUpdateEngines();
+    }
+  }
+
+  private _debouncedUpdateEngines = debounce(() => this._updateEngines(), 500);
+
+  private async _updateEngines() {
+    this._engines = (await listTTSEngines(this.hass, this.language)).providers;
+
+    if (
+      this.value &&
+      !this._engines.find((engine) => engine.engine_id === this.value)
+        ?.language_supported
+    ) {
+      this.value = undefined;
+      fireEvent(this, "value-changed", { value: this.value });
     }
   }
 
@@ -89,11 +110,11 @@ export class HaTTSPicker extends LitElement {
       !this.hass ||
       target.value === "" ||
       target.value === this.value ||
-      (this.value === undefined && target.value === DEFAULT)
+      (this.value === undefined && target.value === NONE)
     ) {
       return;
     }
-    this.value = target.value === DEFAULT ? undefined : target.value;
+    this.value = target.value === NONE ? undefined : target.value;
     fireEvent(this, "value-changed", { value: this.value });
   }
 }
diff --git a/src/panels/config/voice-assistants/dialog-voice-assistant-pipeline-detail.ts b/src/panels/config/voice-assistants/dialog-voice-assistant-pipeline-detail.ts
index 66e5cefa56..3bd1bd00c4 100644
--- a/src/panels/config/voice-assistants/dialog-voice-assistant-pipeline-detail.ts
+++ b/src/panels/config/voice-assistants/dialog-voice-assistant-pipeline-detail.ts
@@ -131,6 +131,7 @@ export class DialogVoiceAssistantPipelineDetail extends LitElement {
         },
         {
           name: "conversation_engine",
+          required: true,
           selector: {
             conversation_agent: {},
           },
diff --git a/src/translations/en.json b/src/translations/en.json
index ffc8b1fd16..6034c59a02 100755
--- a/src/translations/en.json
+++ b/src/translations/en.json
@@ -403,7 +403,7 @@
       },
       "coversation-agent-picker": {
         "conversation_agent": "Conversation agent",
-        "default": "Default agent ({default})"
+        "none": "None"
       },
       "theme-picker": {
         "theme": "Theme",
@@ -411,7 +411,7 @@
       },
       "tts-picker": {
         "tts": "Text to Speech",
-        "default": "Default"
+        "none": "None"
       },
       "user-picker": {
         "no_user": "No user",
@@ -466,7 +466,7 @@
           }
         }
       },
-      "stt-picker": { "stt": "Speech to text", "default": "Default" },
+      "stt-picker": { "stt": "Speech to text", "none": "None" },
       "related-filter-menu": {
         "filter": "Filter",
         "filter_by_entity": "Filter by entity",