diff --git a/include/hardware_caps.h b/include/hardware_caps.h
index 5966056..4904511 100644
--- a/include/hardware_caps.h
+++ b/include/hardware_caps.h
@@ -33,6 +33,9 @@ typedef struct hw_caps
 	display_type_t display_type;
 	int display_xres;	/* x resolution or chars per line */
 	int display_yres;
+#ifdef MARTII
+	int dmx_offset;
+#endif
 	char boxvendor[64];
 	char boxname[64];
 } hw_caps_t;
diff --git a/libspark/dmx.cpp b/libspark/dmx.cpp
index 71f7e17..28bdeac 100644
--- a/libspark/dmx.cpp
+++ b/libspark/dmx.cpp
@@ -56,6 +56,7 @@
 #ifdef MARTII
 #include <unistd.h>
 #include <fcntl.h>
+#include <hardware_caps.h>
 #endif
 
 #include <cstring>
@@ -196,6 +197,9 @@ bool cDemux::_open(void)
 	{
 		/* this should not change anything... */
 		int n = DMX_SOURCE_FRONT0 + devnum;
+#ifdef MARTII
+		n += get_hwcaps()->dmx_offset;
+#endif
 		lt_info("%s: setting %s to source %d\n", __func__, devname[devnum], n);
 		if (ioctl(fd, DMX_SET_SOURCE, &n) < 0)
 			lt_info("%s DMX_SET_SOURCE failed!\n", __func__);
diff --git a/libspark/hardware_caps.c b/libspark/hardware_caps.c
index dda67aa..2bbcfb4 100644
--- a/libspark/hardware_caps.c
+++ b/libspark/hardware_caps.c
@@ -68,6 +68,9 @@ hw_caps_t *get_hwcaps(void)
 				case 0x0c0007:
 					tmp = "GoldenMedia Triplex";
 					caps.has_SCART = 1;
+#ifdef MARTII
+					caps.dmx_offset = 1;
+#endif
 					break;
 				default:
 					tmp = p;