diff --git a/chrome-extension/src/background/chains/solanaHandler.ts b/chrome-extension/src/background/chains/solanaHandler.ts
index f7f20c3..db1ec02 100644
--- a/chrome-extension/src/background/chains/solanaHandler.ts
+++ b/chrome-extension/src/background/chains/solanaHandler.ts
@@ -7,11 +7,46 @@ const TAG = ' | solanaHandler | ';
 
 // Vault REST API and Solana mainnet RPC
 const VAULT_URL = 'http://localhost:1646';
-const SOLANA_RPC_URL = 'https://api.mainnet-beta.solana.com';
+const SOLANA_RPC_URLS = [
+  'https://api.mainnet-beta.solana.com',
+  'https://mainnet.helius-rpc.com/?api-key=1d8740dc-e5f4-421c-b823-e1bad1889eff',
+];
+
+let cachedRpcUrl: string | null = null;
+let cachedRpcTimestamp = 0;
+const RPC_CACHE_TTL = 60000; // cache healthy RPC for 60s
+
+async function getSolanaRpcUrl(): Promise<string> {
+  const now = Date.now();
+  if (cachedRpcUrl && now - cachedRpcTimestamp < RPC_CACHE_TTL) {
+    return cachedRpcUrl;
+  }
+  for (const url of SOLANA_RPC_URLS) {
+    try {
+      const resp = await fetch(url, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ jsonrpc: '2.0', id: 1, method: 'getHealth' }),
+        signal: AbortSignal.timeout(3000),
+      });
+      if (resp.ok) {
+        cachedRpcUrl = url;
+        cachedRpcTimestamp = now;
+        return url;
+      }
+    } catch { /* try next */ }
+  }
+  return SOLANA_RPC_URLS[0]; // fallback to primary
+}
 
 // Cached address from device
 let cachedAddress: string | null = null;
 
+/** Reset cached state (call when device disconnects or wallet re-inits) */
+export function resetSolanaState() {
+  cachedAddress = null;
+}
+
 /** Convert a number[] to base64 string (chunked to avoid call-stack limit) */
 function toBase64(arr: number[]): string {
   const CHUNK = 8192;
@@ -24,7 +59,11 @@ function toBase64(arr: number[]): string {
 
 /** Convert a base64 string to number[] */
 function fromBase64(b64: string): number[] {
-  return Array.from(atob(b64), c => c.charCodeAt(0));
+  try {
+    return Array.from(atob(b64), c => c.charCodeAt(0));
+  } catch (e: any) {
+    throw createProviderRpcError(-32603, `Failed to decode base64 response: ${e.message}`);
+  }
 }
 
 // BIP44 path for Solana: m/44'/501'/0'/0'
@@ -105,7 +144,11 @@ async function requestUserApproval(
 /** Get the Bearer API key from the SDK for direct REST calls */
 function getApiKey(): string {
   const sdk = wallet.getSdk();
-  return sdk.getClient?.()?.getApiKey?.() || '';
+  const key = sdk.getClient?.()?.getApiKey?.();
+  if (!key) {
+    throw createProviderRpcError(-32603, 'API key not available — vault may not be connected');
+  }
+  return key;
 }
 
 /**
@@ -119,17 +162,26 @@ function getApiKey(): string {
  */
 async function signTransactionViaRest(txBase64: string): Promise<{ signature: string; serializedTx: string }> {
   const apiKey = getApiKey();
-  const resp = await fetch(`${VAULT_URL}/solana/sign-transaction`, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
-      Authorization: `Bearer ${apiKey}`,
-    },
-    body: JSON.stringify({
-      raw_tx: txBase64,
-      address_n: SOLANA_ADDRESS_N,
-    }),
-  });
+  let resp: Response;
+  try {
+    resp = await fetch(`${VAULT_URL}/solana/sign-transaction`, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+        Authorization: `Bearer ${apiKey}`,
+      },
+      body: JSON.stringify({
+        raw_tx: txBase64,
+        address_n: SOLANA_ADDRESS_N,
+      }),
+      signal: AbortSignal.timeout(30000),
+    });
+  } catch (e: any) {
+    if (e.name === 'TimeoutError' || e.name === 'AbortError') {
+      throw createProviderRpcError(-32603, 'Vault signing timed out');
+    }
+    throw createProviderRpcError(-32603, `Vault connection failed: ${e.message}`);
+  }
 
   if (!resp.ok) {
     const text = await resp.text().catch(() => '');
@@ -137,13 +189,14 @@ async function signTransactionViaRest(txBase64: string): Promise<{ signature: st
   }
 
   const result = await resp.json();
-  if (!result.signature && !result.serializedTx) {
-    throw createProviderRpcError(-32603, 'Vault returned empty sign result');
+  const serializedTx = result.serializedTx || result.serialized || '';
+  if (!serializedTx) {
+    throw createProviderRpcError(-32603, 'Vault returned no signed transaction data');
   }
 
   return {
     signature: result.signature || '',
-    serializedTx: result.serializedTx || result.serialized || '',
+    serializedTx,
   };
 }
 
@@ -158,17 +211,26 @@ async function signTransactionViaRest(txBase64: string): Promise<{ signature: st
  */
 async function signMessageViaRest(messageBase64: string): Promise<number[]> {
   const apiKey = getApiKey();
-  const resp = await fetch(`${VAULT_URL}/solana/sign-message`, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
-      Authorization: `Bearer ${apiKey}`,
-    },
-    body: JSON.stringify({
-      message: messageBase64,
-      address_n: SOLANA_ADDRESS_N,
-    }),
-  });
+  let resp: Response;
+  try {
+    resp = await fetch(`${VAULT_URL}/solana/sign-message`, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+        Authorization: `Bearer ${apiKey}`,
+      },
+      body: JSON.stringify({
+        message: messageBase64,
+        address_n: SOLANA_ADDRESS_N,
+      }),
+      signal: AbortSignal.timeout(30000),
+    });
+  } catch (e: any) {
+    if (e.name === 'TimeoutError' || e.name === 'AbortError') {
+      throw createProviderRpcError(-32603, 'Vault sign-message timed out');
+    }
+    throw createProviderRpcError(-32603, `Vault connection failed: ${e.message}`);
+  }
 
   if (!resp.ok) {
     const text = await resp.text().catch(() => '');
@@ -191,16 +253,26 @@ async function signMessageViaRest(messageBase64: string): Promise<number[]> {
  * Vault has NO broadcast endpoint — we send directly to Solana RPC.
  */
 async function broadcastTransaction(signedTxBase64: string): Promise<string> {
-  const response = await fetch(SOLANA_RPC_URL, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/json' },
-    body: JSON.stringify({
-      jsonrpc: '2.0',
-      id: 1,
-      method: 'sendTransaction',
-      params: [signedTxBase64, { encoding: 'base64' }],
-    }),
-  });
+  const rpcUrl = await getSolanaRpcUrl();
+  let response: Response;
+  try {
+    response = await fetch(rpcUrl, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        jsonrpc: '2.0',
+        id: 1,
+        method: 'sendTransaction',
+        params: [signedTxBase64, { encoding: 'base64' }],
+      }),
+      signal: AbortSignal.timeout(30000),
+    });
+  } catch (e: any) {
+    if (e.name === 'TimeoutError' || e.name === 'AbortError') {
+      throw createProviderRpcError(-32603, 'Solana RPC broadcast timed out');
+    }
+    throw createProviderRpcError(-32603, `Solana RPC connection failed: ${e.message}`);
+  }
 
   if (!response.ok) {
     throw createProviderRpcError(-32603, `Solana RPC broadcast failed: ${response.status}`);
@@ -306,6 +378,7 @@ export const handleSolanaRequest = async (
           action: 'transaction_complete',
           txHash: txSignature,
           explorerTxLink: 'https://solscan.io/tx/',
+          networkId: 'solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp',
         })
         .catch(() => {});
 
diff --git a/chrome-extension/src/background/index.ts b/chrome-extension/src/background/index.ts
index 5ad8dca..70c3470 100644
--- a/chrome-extension/src/background/index.ts
+++ b/chrome-extension/src/background/index.ts
@@ -7,6 +7,7 @@ globalThis.Buffer = Buffer;
 
 import packageJson from '../../package.json';
 import * as wallet from './wallet';
+import { resetSolanaState } from './chains/solanaHandler';
 import { handleWalletRequest } from './methods';
 import { JsonRpcProvider, formatEther } from 'ethers';
 import { ChainToNetworkId, Chain, COIN_MAP_LONG, shortListSymbolToCaip, NetworkIdToChain } from './chainConfig';
@@ -76,6 +77,11 @@ async function checkKeepKey() {
     if (KEEPKEY_STATE !== 4) {
       console.warn('KeepKey endpoint not found:', error?.message || error);
     }
+    // Clear cached per-chain state when transitioning from connected → disconnected
+    // so a hot-swapped device doesn't sign against a stale cached address.
+    if (prevState === 2 || prevState === 5) {
+      resetSolanaState();
+    }
     KEEPKEY_STATE = 4; // Set state to errored
     updateIcon();
     if (KEEPKEY_STATE !== prevState) pushStateChangeEvent();
@@ -312,6 +318,7 @@ const onStart = async function () {
   const tag = TAG + ' | onStart | ';
   try {
     console.log(tag, 'Starting...');
+    resetSolanaState(); // clear stale cached address before re-init
     await wallet.init();
     console.log(tag, 'Wallet initialized');