diff --git a/ports/espressif/common-hal/wifi/__init__.c b/ports/espressif/common-hal/wifi/__init__.c
index 710688b9d31c..1a4c014bfbc5 100644
--- a/ports/espressif/common-hal/wifi/__init__.c
+++ b/ports/espressif/common-hal/wifi/__init__.c
@@ -212,7 +212,8 @@ void common_hal_wifi_init(bool user_initiated) {
     char cpy_default_hostname[board_len + (MAC_ADDRESS_LENGTH * 2) + 6];
     uint8_t mac[MAC_ADDRESS_LENGTH];
     esp_wifi_get_mac(ESP_IF_WIFI_STA, mac);
-    snprintf(cpy_default_hostname, sizeof(cpy_default_hostname), "cpy-%s-%x", CIRCUITPY_BOARD_ID + board_trim, (unsigned int)mac);
+    snprintf(cpy_default_hostname, sizeof(cpy_default_hostname), "cpy-%s-%02x%02x%02x%02x%02x%02x", CIRCUITPY_BOARD_ID + board_trim, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+
     const char *default_lwip_local_hostname = cpy_default_hostname;
     ESP_ERROR_CHECK(esp_netif_set_hostname(self->netif, default_lwip_local_hostname));
     // set station mode to avoid the default SoftAP
diff --git a/ports/espressif/mpconfigport.mk b/ports/espressif/mpconfigport.mk
index e80c9654040b..ffca0a057436 100644
--- a/ports/espressif/mpconfigport.mk
+++ b/ports/espressif/mpconfigport.mk
@@ -58,6 +58,9 @@ CIRCUITPY_WATCHDOG ?= 1
 CIRCUITPY_WIFI ?= 1
 CIRCUITPY_SOCKETPOOL_IPV6 ?= 1
 
+# Turn off aesio. It is a custom API that no one uses.
+CIRCUITPY_AESIO = 0
+
 # Enable _eve module
 CIRCUITPY__EVE ?= 1