diff --git a/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
index f062638cd..32a5241e0 100644
--- a/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
@@ -1492,6 +1492,8 @@ enum timingMode getTiming() {
 
 /* configure mac */
 
+int getNumberofUDPInterfaces() { return 1; }
+
 void calcChecksum(udp_header *udp) {
     int count = IP_HEADER_SIZE;
     long int sum = 0;
diff --git a/slsDetectorServers/eigerDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/eigerDetectorServer/slsDetectorFunctionList.c
index 5eacd9b6d..4cb71c59b 100644
--- a/slsDetectorServers/eigerDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/eigerDetectorServer/slsDetectorFunctionList.c
@@ -1500,6 +1500,7 @@ enum timingMode getTiming() {
 }
 
 /* configure mac */
+int getNumberofUDPInterfaces() { return 2; }
 
 int getNumberofDestinations(int *retval) {
 #ifdef VIRTUAL
diff --git a/slsDetectorServers/gotthardDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/gotthardDetectorServer/slsDetectorFunctionList.c
index 1fd57beb4..362bf2079 100644
--- a/slsDetectorServers/gotthardDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/gotthardDetectorServer/slsDetectorFunctionList.c
@@ -1299,6 +1299,8 @@ int getExtSignal(int signalIndex) {
 
 /* configure mac */
 
+int getNumberofUDPInterfaces() { return 1; }
+
 void calcChecksum(mac_conf *mac, int sourceip, int destip) {
     mac->ip.ip_ver = 0x4;
     mac->ip.ip_ihl = 0x5;
diff --git a/slsDetectorServers/moenchDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/moenchDetectorServer/slsDetectorFunctionList.c
index 77482af77..c3e9e56b3 100644
--- a/slsDetectorServers/moenchDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/moenchDetectorServer/slsDetectorFunctionList.c
@@ -1157,6 +1157,8 @@ enum timingMode getTiming() {
 
 /* configure mac */
 
+int getNumberofUDPInterfaces() { return 1; }
+
 void calcChecksum(udp_header *udp) {
     int count = IP_HEADER_SIZE;
     long int sum = 0;
diff --git a/slsDetectorServers/mythen3DetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/mythen3DetectorServer/slsDetectorFunctionList.c
index bd4528832..eb5b2ad89 100644
--- a/slsDetectorServers/mythen3DetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/mythen3DetectorServer/slsDetectorFunctionList.c
@@ -1719,6 +1719,8 @@ int getExtSignal(int signalIndex) {
     }
 }
 
+int getNumberofUDPInterfaces() { return 1; }
+
 int configureMAC() {
 
     uint32_t srcip = udpDetails[0].srcip;
diff --git a/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h b/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
index 0506650f6..a868f46a4 100644
--- a/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
+++ b/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
@@ -387,8 +387,8 @@ void calcChecksum(mac_conf *mac, int sourceip, int destip);
 #endif
 #if defined(JUNGFRAUD) || defined(GOTTHARD2D)
 void setNumberofUDPInterfaces(int val);
-int getNumberofUDPInterfaces();
 #endif
+int getNumberofUDPInterfaces();
 
 #if defined(JUNGFRAUD) || defined(EIGERD)
 int getNumberofDestinations(int *retval);
diff --git a/slsDetectorServers/slsDetectorServer/src/slsDetectorServer_funcs.c b/slsDetectorServers/slsDetectorServer/src/slsDetectorServer_funcs.c
index 5c9be68f0..8328e2a18 100644
--- a/slsDetectorServers/slsDetectorServer/src/slsDetectorServer_funcs.c
+++ b/slsDetectorServers/slsDetectorServer/src/slsDetectorServer_funcs.c
@@ -4725,19 +4725,23 @@ void calculate_and_set_position() {
         LOG(logERROR, (mess));
         return;
     }
-    int maxy = maxydet;
-    // position does not change for gotthard2 (2 interfaces)
-#ifdef JUNGFRAUD
-    maxy *= getNumberofUDPInterfaces();
+
+    // calculating new position
+    int numInterfaces = getNumberofUDPInterfaces();
+    int modulePorts[2] = {1, 1};
+    // position does change for eiger and jungfrau (2 interfaces)
+#if defined(EIGERD)
+    modulePorts[1] = numInterfaces; // horz
+#elif defined(JUNGFRAUD)
+    modulePorts[0] = numInterfaces; // vert
 #endif
+    int maxy = maxydet * modulePorts[0];
     int pos[2] = {0, 0};
     // row
     pos[0] = (detectorId % maxy);
     // col for horiz. udp ports
-    pos[1] = (detectorId / maxy);
-#ifdef EIGERD
-    pos[1] *= 2;
-#endif
+    pos[1] = (detectorId / maxy) * modulePorts[1];
+
     LOG(logDEBUG, ("Setting Positions (%d,%d)\n", pos[0], pos[1]));
     if (setDetectorPosition(pos) == FAIL) {
         ret = FAIL;
@@ -4854,7 +4858,6 @@ int is_udp_configured() {
             LOG(logWARNING, ("%s", configureMessage));
             return FAIL;
         }
-#if defined(JUNGFRAUD) || defined(GOTTHARD2D)
         if (getNumberofUDPInterfaces() == 2) {
             if (udpDetails[i].srcip2 == 0) {
                 sprintf(configureMessage,
@@ -4881,7 +4884,6 @@ int is_udp_configured() {
                 return FAIL;
             }
         }
-#endif
     }
     return OK;
 }
@@ -5320,7 +5322,16 @@ int set_num_interfaces(int file_des) {
     LOG(logINFO, ("Setting number of interfaces: %d\n", arg));
 
 #if !defined(JUNGFRAUD) && !defined(GOTTHARD2D)
-    functionNotImplemented();
+    // fixed number of udp interfaces
+    int num_interfaces = getNumberofUDPInterfaces();
+    if (arg != num_interfaces) {
+        ret = FAIL;
+        sprintf(mess,
+                "Could not set number of interfaces. Invalid value: %d. Must "
+                "be %d\n",
+                arg, num_interfaces);
+        LOG(logERROR, (mess));
+    }
 #else
     // only set
     if (Server_VerifyLock() == OK) {
@@ -5380,12 +5391,9 @@ int get_num_interfaces(int file_des) {
     int retval = -1;
     LOG(logDEBUG1, ("Getting number of udp interfaces\n"));
 
-#if !defined(JUNGFRAUD) && !defined(GOTTHARD2D)
-    retval = 1;
-#else
     // get only
     retval = getNumberofUDPInterfaces();
-#endif
+
     LOG(logDEBUG1, ("Number of udp interfaces retval: %u\n", retval));
     return Server_SendResult(file_des, INT32, &retval, sizeof(retval));
 }
@@ -6883,11 +6891,7 @@ int get_receiver_parameters(int file_des) {
 
     // sending real detector parameters
     // udp interfaces
-#if defined(JUNGFRAUD) || defined(GOTTHARD2D)
     i32 = getNumberofUDPInterfaces();
-#else
-    i32 = 1;
-#endif
     n += sendData(file_des, &i32, sizeof(i32), INT32);
     if (n < 0)
         return printSocketReadError();
@@ -9025,10 +9029,7 @@ int set_dest_udp_list(int file_des) {
                 }
 
                 // if still 0, set defaults
-                int twoInterfaces = 0;
-#if defined(JUNGFRAUD) || defined(GOTTHARD2D)
-                twoInterfaces = getNumberofUDPInterfaces() == 2 ? 1 : 0;
-#endif
+                int twoInterfaces = getNumberofUDPInterfaces() == 2 ? 1 : 0;
                 udpDetails[entry].srcport = DEFAULT_UDP_SRC_PORTNO;
                 if (udpDetails[entry].dstport == 0) {
                     udpDetails[entry].dstport =