Memory Leak at characteristicvaluechanged

Hello,

I am trying to communicate with another device over Bluetooth.
But everytime I receive a packet on the Puck.js it uses memory and don't release it.
So after a few packets, the memory becomes less an I get an error Message --> MEMORY_BUSY.
On the Screenshot you can see how the memory decreases. (it starts a 1800 free blocks)
After I got the MEMORY_BUSY message it no longer receive every packet, so I miss most of the packets.

I think there must be a Memory Leak in the "characteristicvaluechanged" function
Do someone have simular problems and have found a solution for this problem ?

  NRF.connect("00:13:43:0A:EE:79").then(
    function(d) {
      print("connected");
      device = d;
      return device.getPrimaryService("180D");
    }
  ).then(
    function(s){
      service = s;
      return service.getCharacteristic("2A37");
    }
  ).then(
    function(rd){
      read_char = rd;
      read_char.on('characteristicvaluechanged­', function(e) {
        print("received");
        print(process.memory().free);
        event = e;
      });
      return read_char.startNotifications();
    }
  );

1 Attachment