diff --git a/src/cell_dir.rs b/src/cell_dir.rs
index 7c71edd..a52669d 100644
--- a/src/cell_dir.rs
+++ b/src/cell_dir.rs
@@ -73,6 +73,73 @@ impl CellDir {
         }
     }
 
+    pub fn path_from_to(mut a: (usize, usize), b: (usize, usize))
+        -> Vec<CellDir>
+    {
+        let mut path = vec![];
+
+        let mut defensive_max : i32 = 1024;
+
+        while (a.0 != b.0 || a.1 != b.1) && defensive_max > 0 {
+            //d// println!("ITER START: A={:?} B={:?}", a, b);
+            defensive_max -= 1;
+
+            let mut min_distance = 99999.0;
+            let mut min_dir      = CellDir::C;
+            let mut min_new_a    = a;
+
+            for e in 0..6 {
+                let dir = Self::from(e);
+
+                if let Some(new_pos) = dir.offs_pos(a) {
+                    let dist = 
+                          (b.0 as f32 - new_pos.0 as f32).powf(2.0)
+                        + (b.1 as f32 - new_pos.1 as f32).powf(2.0);
+
+                    //d// println!("DIST={:5.3} FOR {:?} (B={:?})", dist, new_pos, b);
+
+                    if dist < min_distance {
+                        min_distance = dist;
+                        min_dir      = dir;
+                        min_new_a    = new_pos;
+                    }
+                } else {
+                    //d// println!("NOPOS {:?} {:?}", dir, a);
+                }
+            }
+
+            if min_distance < 99999.0 {
+                //d// println!("A={:?} => {:?} DIR={:?} B={:?}", a, min_new_a, min_dir, b);
+                a = min_new_a;
+                path.push(min_dir);
+            } else {
+                //d// println!("ITER BREAK");
+                break;
+            }
+
+            //d// println!("ITER END: A={:?} B={:?} MAX={}", a, b, defensive_max);
+        }
+
+        //d// println!("PATH: {:?}", path);
+
+        path
+    }
+
+    pub fn offs_pos(&self, pos: (usize, usize)) -> Option<(usize, usize)> {
+        let offs = self.as_offs(pos.0);
+
+        let new_pos = (
+            pos.0 as i32 + offs.0,
+            pos.1 as i32 + offs.1
+        );
+
+        if new_pos.0 >= 0 && new_pos.1 >= 0 {
+            Some((new_pos.0 as usize, new_pos.1 as usize))
+        } else {
+            None
+        }
+    }
+
     pub fn as_offs(&self, x: usize) -> (i32, i32) {
         let even = x % 2 == 0;
         match self {
diff --git a/src/matrix.rs b/src/matrix.rs
index 1fc3420..6f59125 100644
--- a/src/matrix.rs
+++ b/src/matrix.rs
@@ -36,7 +36,7 @@ use std::collections::{HashMap, HashSet};
 ///
 /// matrix.sync().unwrap();
 ///```
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
 pub struct Cell {
     node_id:  NodeId,
     x:        u8,
@@ -178,6 +178,20 @@ impl Cell {
         (self.x as usize, self.y as usize)
     }
 
+    pub fn offs_dir(&mut self, dir: CellDir) -> bool {
+        if let Some(new_pos) =
+            dir.offs_pos((self.x as usize, self.y as usize))
+        {
+            self.x = new_pos.0 as u8;
+            self.y = new_pos.1 as u8;
+            true
+        }
+        else
+        {
+            false
+        }
+    }
+
     pub fn has_dir_set(&self, dir: CellDir) -> bool {
         match dir {
             CellDir::TR => self.out1.is_some(),
@@ -258,6 +272,8 @@ pub enum MatrixError {
         output1: (NodeId, u8),
         output2: (NodeId, u8),
     },
+    NonEmptyCell { cell: Cell },
+    PosOutOfRange
 }
 
 /// An intermediate data structure to store a single edge in the [Matrix].
@@ -443,6 +459,58 @@ impl Matrix {
         }
     }
 
+    /// Like [Matrix::change_matrix] but the function passed to this
+    /// needs to return a `Result<(), MatrixError>`.
+    pub fn change_matrix_err<F>(&mut self, mut f: F)
+        -> Result<(), MatrixError>
+        where F: FnMut(&mut Self) -> Result<(), MatrixError>
+    {
+        self.save_matrix();
+
+        if let Err(e) = f(self) {
+            self.restore_matrix();
+            return Err(e);
+        }
+
+        if let Err(e) = self.check() {
+            self.restore_matrix();
+            Err(e)
+        } else {
+            Ok(())
+        }
+    }
+
+    /// Tries to place all `cells` at once, if they are placed in empty
+    /// cells only! Returns an error of the destination cell is not empty
+    /// or out of range, or if the placement of the cluster results in any
+    /// other inconsistencies.
+    ///
+    /// This action must be wrapped with [Matrix::change_matrix_err]!
+    ///
+    /// Restores the matrix to the previous state if placing fails.
+    pub fn place_multiple(&mut self, cells: &[Cell]) -> Result<(), MatrixError> {
+        for cell in cells {
+            let x = cell.pos().0;
+            let y = cell.pos().1;
+
+            if let Some(existing) = self.get(x, y) {
+                if !existing.is_empty() {
+                    return Err(MatrixError::NonEmptyCell { cell: *existing });
+                }
+
+                self.place(x, y, *cell);
+            } else {
+                return Err(MatrixError::PosOutOfRange);
+            }
+        }
+
+        if let Err(e) = self.check() {
+            Err(e)
+        } else {
+            Ok(())
+        }
+    }
+
     /// Inserts a cell into the hexagonal grid of the matrix.
     /// You have to make sure that the resulting DSP graph topology
     /// does not have cycles, otherwise an upload to the DSP thread via
diff --git a/src/nodes/node_exec.rs b/src/nodes/node_exec.rs
index f665de7..d64d28d 100644
--- a/src/nodes/node_exec.rs
+++ b/src/nodes/node_exec.rs
@@ -17,6 +17,12 @@ use crate::log;
 use ringbuf::{Producer, Consumer};
 use std::sync::Arc;
 
+use core::arch::x86_64::{
+    _MM_FLUSH_ZERO_ON,
+    _MM_SET_FLUSH_ZERO_MODE,
+//    _MM_GET_FLUSH_ZERO_MODE
+};
+
 /// Holds the complete allocation of nodes and
 /// the program. New Nodes or the program is
 /// not newly allocated in the audio backend, but it is
@@ -256,6 +262,8 @@ impl NodeExecutor {
                 GraphMessage::NewProg { prog, copy_old_out } => {
                     let mut prev_prog = std::mem::replace(&mut self.prog, prog);
 
+                    unsafe { _MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON); }
+
                     self.monitor_signal_cur_inp_indices =
                         [UNUSED_MONITOR_IDX; MON_SIG_CNT];