diff --git a/asciinema/compose.yaml b/asciinema/compose.yaml
index 6f7acc2..72a5df1 100644
--- a/asciinema/compose.yaml
+++ b/asciinema/compose.yaml
@@ -20,6 +20,7 @@ services:
       SMTP_PASSWORD: ${EMAIL_SMTP_PASSWORD}
       SMTP_SSL: true
       SMTP_RETRIES: 2
+      SMTP_NO_MX_LOOKUPS: true
       MAIL_FROM_ADDRESS: ${EMAIL_FROM}
       MAIL_REPLY_TO_ADDRESS: ${ASCIINEMA_MAIL_REPLY_TO}
       SIGN_UP_DISABLED: ${ASCIINEMA_SIGN_UP_DISABLED:-false}