diff --git a/firmware/ice40-riscv/icE1usb/usb_e1.c b/firmware/ice40-riscv/icE1usb/usb_e1.c
index 34ade71..09b428c 100644
--- a/firmware/ice40-riscv/icE1usb/usb_e1.c
+++ b/firmware/ice40-riscv/icE1usb/usb_e1.c
@@ -375,7 +375,7 @@
 		return _e1_ctrl_req_dev(req, xfer);
 	case USB_REQ_RCPT_INTF:
 		if (req->wIndex != 0)
-			return USB_FND_ERROR;
+			return USB_FND_CONTINUE;
 		return _e1_ctrl_req_intf(req, xfer);
 	case USB_REQ_RCPT_EP:
 	case USB_REQ_RCPT_OTHER: