diff --git a/config_rtl.py b/config_rtl.py
index c759978..99bc5b8 100755
--- a/config_rtl.py
+++ b/config_rtl.py
@@ -70,7 +70,7 @@ Example DSP commands:
   * Decompress FLAC-coded I/Q data:
     flac --force-raw-format --decode --endian=little --sign=unsigned - -
 '''
-watchdog_interval=1.5
+watchdog_interval=0
 reconnect_interval=10 
 '''
 If there's no input I/Q data after N seconds, input will be filled with zero samples, 
diff --git a/config_webrx.py b/config_webrx.py
index 230e349..f4f3de5 100755
--- a/config_webrx.py
+++ b/config_webrx.py
@@ -53,7 +53,7 @@ center_freq = 145525000
 rf_gain = 5
 
 start_rtl_thread=True #rtl_sdr is more stable than rtl_tcp...
-start_rtl_command="rtl_sdr -s {samp_rate} -f {center_freq}  - | nc -vvl 127.0.0.1 -p 8888".format(rf_gain=rf_gain, center_freq=center_freq, samp_rate=samp_rate) 
+start_rtl_command="rtl_sdr -s {samp_rate} -f {center_freq} - | nc -vvl 127.0.0.1 -p 8888".format(rf_gain=rf_gain, center_freq=center_freq, samp_rate=samp_rate) 
 #start_rtl_tcp_command="rtl_tcp -s 250000 -f 145525000 -g 0 -p 8888"
 #You can use other SDR hardware as well, but if the command above outputs samples in a format other than [unsigned char], then the dsp plugin has to be slightly modified (at the csdr convert_u8_f part).
 
diff --git a/htdocs/openwebrx.js b/htdocs/openwebrx.js
index 3947f5d..b62ac66 100755
--- a/htdocs/openwebrx.js
+++ b/htdocs/openwebrx.js
@@ -1297,8 +1297,8 @@ var color_scale=[0x2e6893ff, 0x69a5d0ff, 0x214b69ff, 0x9dc4e0ff,  0xfff775ff, 0x
 
 function waterfall_mkcolor(db_value)
 {
-	min_value=-100; //in dB
-	max_value=10
+	min_value=-115; //in dB
+	max_value=0
 	if(db_value<min_value) db_value=min_value
 	if(db_value>max_value) db_value=max_value
 	full_scale=max_value-min_value;
diff --git a/openwebrx.py b/openwebrx.py
index 37e09e4..1d7b44a 100755
--- a/openwebrx.py
+++ b/openwebrx.py
@@ -219,6 +219,7 @@ def generate_client_id(ip):
 	new_client.spectrum_queue=Queue.Queue(1000)
 	new_client.ip=ip
 	new_client.closed=[False] #byref, not exactly sure if required
+	new_client.dsp=None
 	clients_mutex.acquire()
 	clients.append(new_client)
 	log_client(new_client,"client added. Clients now: {0}".format(len(clients)))
@@ -231,6 +232,12 @@ def close_client(i, use_mutex=True):
 	global clients
 	log_client(clients[i],"client being closed.")
 	if use_mutex: clients_mutex.acquire()
+	try:
+		clients[i].dsp.stop()
+	except:
+		exc_type, exc_value, exc_traceback = sys.exc_info()
+		print "[openwebrx] close_client dsp.stop() :: error -",exc_type,exc_value
+		traceback.print_tb(exc_traceback)
 	clients[i].closed[0]=True
 	del clients[i]
 	if use_mutex: clients_mutex.release()
@@ -289,6 +296,7 @@ class WebRXHandler(BaseHTTPRequestHandler):
 					dsp.set_offset_freq(0)
 					dsp.set_bpf(-4000,4000)
 					dsp.start()
+					myclient.dsp=dsp
 					
 					while True:
 						if myclient.closed[0]: 
diff --git a/plugins/dsp/csdr/plugin.py b/plugins/dsp/csdr/plugin.py
index 01e6eec..f2b0aac 100644
--- a/plugins/dsp/csdr/plugin.py
+++ b/plugins/dsp/csdr/plugin.py
@@ -2,6 +2,7 @@ import subprocess
 import time
 import os
 import code
+import signal
 
 class dsp_plugin:
 
@@ -26,7 +27,7 @@ class dsp_plugin:
 		self.demodulator = "nfm"
 		self.name = "csdr"
 		try:	
-			subprocess.Popen("nc",stdout=subprocess.PIPE,stderr=subprocess.PIPE)
+			subprocess.Popen("nc",stdout=subprocess.PIPE,stderr=subprocess.PIPE).kill()
 		except:
 			print "[openwebrx-plugin:csdr] error: netcat not found, please install netcat!"
 
@@ -106,7 +107,7 @@ class dsp_plugin:
 		command=command_base.format(bpf_pipe=self.bpf_pipe,shift_pipe=self.shift_pipe,decimation=self.decimation,last_decimation=self.last_decimation,fft_size=self.fft_size,fft_block_size=self.fft_block_size(),bpf_transition_bw=float(self.bpf_transition_bw)/self.if_samp_rate(),ddc_transition_bw=self.ddc_transition_bw())
 		print "[openwebrx-dsp-plugin:csdr] Command =",command
 		#code.interact(local=locals())
-		self.process = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True)
+		self.process = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True, preexec_fn=os.setpgrp)
 		self.running = True
 
 		#open control pipes for csdr and send initialization data
@@ -121,10 +122,7 @@ class dsp_plugin:
 		return self.process.stdout.read(size)
 		
 	def stop(self):
-		if(self.process!=None):return # returns None while subprocess is running
-		while(self.process.poll()==None):
-			self.process.kill()
-			time.sleep(0.1)
+		os.killpg(os.getpgid(self.process.pid), signal.SIGTERM) 
 		os.unlink(self.bpf_pipe)
 		os.unlink(self.shift_pipe)
 		self.running = False
diff --git a/rtl_mus.py b/rtl_mus.py
index c244380..3193165 100644
--- a/rtl_mus.py
+++ b/rtl_mus.py
@@ -87,7 +87,7 @@ def add_data_to_clients(new_data):
 			elif cfg.cache_full_behaviour == 1:
 				#rather closing client:
 				log.error("client cache full, dropping client: "+str(client[0].ident)+"@"+client[0].socket[1][0])
-				client[0].close()
+				client[0].close(False)
 			elif cfg.cache_full_behaviour == 2:
 				pass #client cache full, just not taking care
 			else: log.error("invalid value for cfg.cache_full_behaviour")
@@ -131,6 +131,7 @@ class client_handler(asyncore.dispatcher):
 		self.sent_dongle_id=False
 		self.last_waiting_buffer=""
 		asyncore.dispatcher.__init__(self, self.client[0].socket[0])
+		self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
 
 	def handle_read(self):
 		global commands
@@ -174,6 +175,7 @@ class server_asyncore(asyncore.dispatcher):
 		self.set_reuse_addr()
 		self.bind((cfg.my_ip, cfg.my_listening_port))
 		self.listen(5)
+		self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
 		log.info("Server listening on port: "+str(cfg.my_listening_port))
 
 	def handle_accept(self):
@@ -188,7 +190,7 @@ class server_asyncore(asyncore.dispatcher):
 			my_client[0].ident=max_client_id
 			max_client_id+=1
 			my_client[0].start_time=time.time()
-			my_client[0].waiting_data=multiprocessing.Queue(250)
+			my_client[0].waiting_data=multiprocessing.Queue(500)
 			clients_mutex.acquire()
 			clients.append(my_client)
 			clients_mutex.release()
@@ -278,9 +280,9 @@ class rtl_tcp_asyncore(asyncore.dispatcher):
 		if(len(rtl_dongle_identifier)==0):
 			rtl_dongle_identifier=self.recv(12)
 			return
-		new_data_buffer=self.recv(16348)
+		new_data_buffer=self.recv(1024*16)
 		if cfg.watchdog_interval:
-			watchdog_data_count+=16348
+			watchdog_data_count+=1024*16
 		if cfg.use_dsp_command:
 			dsp_input_queue.put(new_data_buffer)
 			#print "did put anyway"
@@ -418,11 +420,13 @@ class client:
 	socket=None
 	asyncore=None
 
-	def close(self):
+	def close(self, use_mutex=True):
 		global clients_mutex
 		global clients
-		clients_mutex.acquire()
+		if use_mutex: clients_mutex.acquire()
+		correction=0
 		for i in range(0,len(clients)):
+			i-=correction
 			if clients[i][0].ident==self.ident:
 				try:
 					self.socket.close()
@@ -433,8 +437,9 @@ class client:
 					del self.asyncore
 				except:
 					pass
-				break
-		clients_mutex.release()
+				del clients[i]
+				correction+=1
+		if use_mutex: clients_mutex.release()
 
 
 def main():