--- soundcard/ptt.c.orig	2013-08-13 19:39:10.718911416 -0700
+++ soundcard/ptt.c	2013-08-13 19:40:49.013576217 -0700
@@ -348,10 +348,8 @@
 #else
 		unsigned int y;
 		ioctl(state->u.fd, TIOCMGET, &y);
-		if (state->dcd)
-		    y |= TIOCM_DTR;
-		else
-		    y &= ~TIOCM_DTR;
+                /* Disable the DCD from asserting DTR on the serial interface used for PTT */
+		y &= ~TIOCM_DTR; /* this unsets DTR */
 		ioctl(state->u.fd, TIOCMSET, &y);
 #endif
 		return;