diff --git a/AGENTS.md b/AGENTS.md
index 30f0850..d1125fb 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -512,7 +512,18 @@ session with **no other memory of this project**. So:
     **legacy/unsigned** posts in a 30 s loop with **no interactive gate** — it now
     skips unsigned posts for interactive signers (pre-signed ones still publish).
     ⚠️ If you add a new read hook that decrypts, gate it the same way or Amber
-    will storm on every navigation. (Not yet done: a persisted decrypt cache, so
+    will storm on every navigation. ⚠️ **Never fire concurrent signer intents with
+    an interactive signer (fixed 2026-10-13).** `useSendDirectMessage` created the
+    per-recipient gift wraps with `Promise.all`, and `sealGroupMessage`
+    (`lib/cordn/crypto.ts`) encrypted to the whole roster with `Promise.all`. Amber
+    is a single foreground activity: several `nostrsigner:` intents at once means
+    only one is answered, and the others sit until the **60 s** `TIMEOUT_MS` in
+    `android-templates/AmberIntentPlugin.java` rejects with the misleading *"Amber
+    didn't respond. Make sure Amber is installed"*. Both now send **sequentially
+    for an interactive signer** (parallel kept for silent ones); the NIP-17 crew
+    Chat therefore costs **2 approvals per member** (encrypt + sign). Steering
+    Amber users to the **MLS Private chat** (≈1 approval per action) is the real
+    cure. (Not yet done: a persisted decrypt cache, so
     the first load per app start still decrypts everything.)
   - **Sasquatch AI guide** (`src/components/SasquatchGuide.tsx`): the chat
     queries public relays **directly** (`useCVMClient.ts`, 3 fixed relays) and
diff --git a/src/hooks/useDirectMessages.ts b/src/hooks/useDirectMessages.ts
index b2f9c65..bf2d46b 100644
--- a/src/hooks/useDirectMessages.ts
+++ b/src/hooks/useDirectMessages.ts
@@ -225,6 +225,7 @@ function createRumor(
 export function useSendDirectMessage() {
   const { nostr } = useNostr();
   const { user } = useCurrentUser();
+  const { logins } = useNostrLogin();
   const { config } = useAppContext();
   const { write } = useRelays();
   const queryClient = useQueryClient();
@@ -292,7 +293,18 @@ export function useSendDirectMessage() {
 
     // 3. Create gift wraps for all recipients AND sender (so sender sees own messages)
     const allTargets = [...new Set([...recipients, user.pubkey])];
-    const giftWraps = await Promise.all(allTargets.map(createSealAndWrap));
+    // Each wrap costs TWO interactive signer ops (encrypt the rumor, sign the
+    // seal). An interactive signer (Amber) opens a foreground activity per op —
+    // firing them in parallel launches several intents at once, only one gets
+    // answered, and the rest time out ("Amber didn't respond"). So for Amber we
+    // MUST do them one at a time; silent signers keep the fast parallel path.
+    const interactive = isInteractiveSigner(user, logins);
+    const giftWraps: NostrEvent[] = [];
+    if (interactive) {
+      for (const target of allTargets) giftWraps.push(await createSealAndWrap(target));
+    } else {
+      giftWraps.push(...(await Promise.all(allTargets.map(createSealAndWrap))));
+    }
 
     // 4. Work out where to deliver. NIP-17: publish the wrap to each
     //    RECIPIENT's inbox relays (their kind 10050), plus our own inbox so we
@@ -401,7 +413,7 @@ export function useSendDirectMessage() {
       queryClient.invalidateQueries({ queryKey: ['group-conversations'] });
     }
 
-  }, [user, nostr, config, write, queryClient]);
+  }, [user, logins, nostr, config, write, queryClient]);
 
   return useMutation({
     mutationFn: async ({ recipients, content, replyTo, subject }: {
diff --git a/src/i18n/en.ts b/src/i18n/en.ts
index a6968ac..a98dccd 100644
--- a/src/i18n/en.ts
+++ b/src/i18n/en.ts
@@ -4523,7 +4523,7 @@ settingsUi: {
       defaultAction: 'send',
       multiBefore: 'Your signer will ask you to approve',
       multiTimes: '{{approvals}} times',
-      multiAfter: 'to {{action}} — that\'s normal for encrypted messages (one approval per recipient). Approve each.',
+      multiAfter: 'to {{action}} — that\'s normal for encrypted messages (an encrypt + a signature per member). Approve each.',
       single: 'Your signer will ask you to approve to {{action}}.',
     },
     amberCallback: {
diff --git a/src/i18n/es.ts b/src/i18n/es.ts
index bcb4080..58acfc7 100644
--- a/src/i18n/es.ts
+++ b/src/i18n/es.ts
@@ -4523,7 +4523,7 @@ settingsUi: {
       defaultAction: 'enviar',
       multiBefore: 'Tu firmador te pedirá que apruebes',
       multiTimes: '{{approvals}} veces',
-      multiAfter: 'para {{action}} — es normal en los mensajes cifrados (una aprobación por destinatario). Aprueba cada una.',
+      multiAfter: 'para {{action}} — es normal en los mensajes cifrados (un cifrado y una firma por miembro). Aprueba cada una.',
       single: 'Tu firmador te pedirá que apruebes para {{action}}.',
     },
     amberCallback: {
diff --git a/src/lib/cordn/crypto.ts b/src/lib/cordn/crypto.ts
index 801a0fc..d646618 100644
--- a/src/lib/cordn/crypto.ts
+++ b/src/lib/cordn/crypto.ts
@@ -109,13 +109,14 @@ export async function sealGroupMessage(
   const json = JSON.stringify(plaintext);
 
   // Encrypt once per unique recipient (roster ∪ {sender}).
+  // ⚠️ Serial, not Promise.all: with an interactive signer (Amber) each encrypt
+  // opens a foreground activity, and concurrent intents collide/time out
+  // ("Amber didn't respond"). For a silent signer the cost is negligible.
   const targets = Array.from(new Set([senderPk.toLowerCase(), ...roster.map((r) => r.toLowerCase())]));
   const recipients: Record<string, string> = {};
-  await Promise.all(
-    targets.map(async (pk) => {
-      recipients[pk] = await signer.nip44.encrypt(pk, json);
-    }),
-  );
+  for (const pk of targets) {
+    recipients[pk] = await signer.nip44.encrypt(pk, json);
+  }
 
   return { v: 2, alg: 'nip44-group-v2', recipients };
 }