diff --git a/apps/machine/src/stores/atm.ts b/apps/machine/src/stores/atm.ts
index fd00df2..c868322 100644
--- a/apps/machine/src/stores/atm.ts
+++ b/apps/machine/src/stores/atm.ts
@@ -306,6 +306,22 @@ export const useAtmStore = defineStore('atm', () => {
   // screen (raw lnurlw, spent by this call) or the session opened at entry
   // (hit-keyed steps, no p/c).
   type BoltCardSource = { lnurlw: string } | { session: CardSession }
+  // Electron IPC structured-clones its arguments and rejects Vue reactive
+  // proxies with "An object could not be cloned". `loadedBoltCard` is a ref,
+  // so anything reached through it is a proxy — copy the steps field by field
+  // into plain objects before they cross the bridge.
+  const plainWithdrawStep = (w: NonNullable<CardSession['withdraw']>) => ({
+    callback: w.callback,
+    k1: w.k1,
+    minWithdrawable: w.minWithdrawable,
+    maxWithdrawable: w.maxWithdrawable,
+  })
+  const plainPayStep = (p: CardSession['pay']) => ({
+    callback: p.callback,
+    minSendable: p.minSendable,
+    maxSendable: p.maxSendable,
+    metadata: p.metadata,
+  })
   // Access-control gate config (ADR-003). Defaults disabled → the machine's
   // `locked` state bypasses straight to `idle` (behaviour identical to no gate).
   // Populated from RuntimeConfig.accessControl in initializeForProduction.
@@ -327,6 +343,10 @@ export const useAtmStore = defineStore('atm', () => {
   // The card balance is hidden by default on the public screen; the holder
   // reveals it with the eye toggle. Resets on re-lock.
   const cardBalanceRevealed = ref(false)
+  // When the card server names a currency but didn't price the balance (its
+  // rate cache was cold — it never blocks the unlock on a rate lookup), price
+  // it here from the ATM's own rate source, in that currency.
+  const cardFiatRate = ref<{ currency: string; btcPrice: number } | null>(null)
   const fiatCode = ref('USD')
   // Defaults are 0 — the operator's fee config (received via Nostr
   // kind-30078 `bitspire-fees:<atm_pubkey>` envelope from satmachineadmin)
@@ -472,6 +492,10 @@ export const useAtmStore = defineStore('atm', () => {
     const card = loadedBoltCard.value
     if (!card) return null
     if (card.currency && card.fiat !== null) return { amount: card.fiat, currency: card.currency }
+    const rate = cardFiatRate.value
+    if (card.currency && rate && rate.currency === card.currency) {
+      return { amount: (card.balanceSats / 1e8) * rate.btcPrice, currency: card.currency }
+    }
     if (btcPrice.value && btcPrice.value > 0) {
       return { amount: (card.balanceSats / 1e8) * btcPrice.value, currency: fiatCode.value }
     }
@@ -540,6 +564,7 @@ export const useAtmStore = defineStore('atm', () => {
       if (state === 'locked' && loadedBoltCard.value) {
         loadedBoltCard.value = null
         cardBalanceRevealed.value = false
+        cardFiatRate.value = null
       }
 
       // Detect network from first invoice we see
@@ -673,7 +698,7 @@ export const useAtmStore = defineStore('atm', () => {
         'session' in source
           ? source.session.withdraw
             ? await api.withdrawWithSession({
-                withdraw: source.session.withdraw,
+                withdraw: plainWithdrawStep(source.session.withdraw),
                 bolt11: invoice,
                 amountMsat,
               })
@@ -713,7 +738,7 @@ export const useAtmStore = defineStore('atm', () => {
       const api = window.electronAPI!
       const res =
         'session' in source
-          ? await api.resolveSessionInvoice({ pay: source.session.pay, amountMsat })
+          ? await api.resolveSessionInvoice({ pay: plainPayStep(source.session.pay), amountMsat })
           : await api.resolveCardInvoice({ lnurlw: source.lnurlw, amountMsat })
       if (!res.ok || !res.bolt11) {
         boltCardProcessing.value = false
@@ -763,7 +788,14 @@ export const useAtmStore = defineStore('atm', () => {
     boltCardProcessing.value = true
     nfcStatus.value = { state: 'processing', message: 'Verifying card…' }
     try {
+      const t0 = Date.now()
       const opened = await window.electronAPI.openCardSession({ lnurlw })
+      console.info(
+        `[ATM] Card session ${opened.ok ? 'opened' : 'refused'} in ${Date.now() - t0} ms` +
+          (opened.ok
+            ? ` (fiat ${opened.session.fiat === null ? 'not ' : ''}priced by card server)`
+            : '')
+      )
       if (!opened.ok) {
         nfcStatus.value = { state: 'declined', message: opened.reason }
         denyAccess(opened.reason)
@@ -777,8 +809,18 @@ export const useAtmStore = defineStore('atm', () => {
       if (outcome.status === 'granted') {
         loadedBoltCard.value = opened.session
         cardBalanceRevealed.value = false
+        cardFiatRate.value = null
         nfcStatus.value = { state: 'accepted', message: 'Card accepted' }
         grantAccess(outcome.role, outcome.credentialIdHash)
+        // Price the balance in the card's currency off the unlock path.
+        const { currency, fiat, externalId } = opened.session
+        if (currency && fiat === null) {
+          void fetchBtcPrice(currency).then((price) => {
+            if (price && loadedBoltCard.value?.externalId === externalId) {
+              cardFiatRate.value = { currency, btcPrice: price }
+            }
+          })
+        }
       } else {
         // pin-required can't occur for card-only open-enrollment; treat as denied.
         const reason = outcome.status === 'denied' ? outcome.reason : 'card not authorized'
diff --git a/docs/boltcard-session.md b/docs/boltcard-session.md
index 2daa775..e93242a 100644
--- a/docs/boltcard-session.md
+++ b/docs/boltcard-session.md
@@ -63,9 +63,11 @@ one `hit` is recorded.
 - `balance_msat` — the card wallet's balance. Display only.
 - `currency` / `fiat` — the balance priced the way the LNbits wallet page does
   it: the wallet's own currency (per-wallet setting) first, else the instance's
-  default accounting currency, at the server's rate. `null` when the server has
-  no currency or the rate lookup failed; the ATM then prices the sats itself in
-  its own fiat at its display rate. A rate failure never fails the session.
+  default accounting currency. `fiat` is filled **only from the server's
+  already-warm rate cache** — this response gates the unlock, and a cold rate
+  lookup queries external exchanges (~1 s). On a cache miss it is `null` and
+  the ATM prices the sats itself: in `currency` from its own rate source, else
+  in its own fiat at its display rate. No rate lookup ever blocks the session.
 - `withdraw` — the LUD-03 second step. The ATM calls
   `callback?k1=<hit>&pr=<bolt11>` at cash-out Complete. `null` with
   `withdraw_blocked_reason` set when `/scan` would have refused (daily limit