diff --git a/cryptopiaAPI.php b/cryptopiaAPI.php
index f00aecb..d25c939 100644
--- a/cryptopiaAPI.php
+++ b/cryptopiaAPI.php
@@ -36,7 +36,7 @@ private function apiCall($method, array $req = array()) {
          curl_setopt($ch, CURLOPT_URL, $url );
       } elseif ( in_array( $method, $private_set ) ) {
          $url = "https://www.cryptopia.co.nz/Api/" . $method;
-         $nonce = explode(' ', microtime())[1];
+         $nonce = base64_encode(random_bytes(128));
          $post_data = json_encode( $req );
          $m = md5( $post_data, true );
          $requestContentBase64String = base64_encode( $m );
diff --git a/exchange.php b/exchange.php
index 9f84793..b2df4b3 100644
--- a/exchange.php
+++ b/exchange.php
@@ -58,7 +58,7 @@ public function getSymbols() {
    // note: $exchangeSymbol must be have the base currency first and quote currency second (i.e. eth_btc Not btc_eth). The quote currency is usually BTC, USD, or CNY.
    public function makeStandardSymbol($exchangeSymbol) {
       // Convert to Uppercase and remove nonletters.
-      return preg_replace('/[^A-Z]/', '', strtoupper ( $exchangeSymbol )); 
+      return $exchangeSymbol; 
    }
    // @todo not implemented for all exchanges, setSymbols() must create associative array $this->symbols with keys as standard symbols and  values as exchange symbols for this function to work.
    public function getExchangeSymbol($standardSymbol) {