diff --git a/src/oceanic_atom2.c b/src/oceanic_atom2.c
index d6183ae..b18791a 100644
--- a/src/oceanic_atom2.c
+++ b/src/oceanic_atom2.c
@@ -165,7 +165,7 @@ oceanic_atom2_init (oceanic_atom2_device_t *device)
 	}
 
 	// Receive the answer of the dive computer.
-	unsigned char answer[3] = {0};
+	unsigned char answer[1] = {0};
 	n = serial_read (device->port, answer, sizeof (answer));
 	if (n != sizeof (answer)) {
 		WARNING ("Failed to receive the answer.");
@@ -173,7 +173,7 @@ oceanic_atom2_init (oceanic_atom2_device_t *device)
 	}
 
 	// Verify the answer.
-	if (answer[0] != NAK || answer[1] != NAK || answer[2] != NAK) {
+	if (answer[0] != NAK) {
 		WARNING ("Unexpected answer byte(s).");
 		return DEVICE_STATUS_PROTOCOL;
 	}
@@ -273,6 +273,9 @@ oceanic_atom2_device_open (device_t **out, const char* name)
 		return status;
 	}
 
+	// Make sure everything is in a sane state.
+	serial_flush (device->port, SERIAL_QUEUE_BOTH);
+
 	// Switch the device from surface mode into download mode. Before sending
 	// this command, the device needs to be in PC mode (automatically activated
 	// by connecting the device), or already in download mode.