Raspberry GPIO email script - Raspberry Pi Development

Hi,
I made a simple script that sends me an email when the raspberry detects a rising signal on a gpio input
Between the switch and the gpio i have mounted a resistor (1K ohm all connections are soldered) to prevent the gpio from flaoting
Script works well but when it is up and running for about 15min the RPI detects a rising signal?
Can someone help me out?
greets kawa
Script:
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import smtplib
import time
def sendemail(from_addr, to_addr_list, cc_addr_list,
subject, message,
login, password,
smtpserver='smtp.gmail.com:587'):
header = 'From: %s\n' % from_addr
header += 'To: %s\n' % ','.join(to_addr_list)
header += 'Cc: %s\n' % ','.join(cc_addr_list)
header += 'Subject: %s\n\n' % subject
message = header + message
server = smtplib.SMTP(smtpserver)
server.starttls()
server.login(login,password)
problems = server.sendmail(from_addr, to_addr_list, message)
server.quit()
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(23, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
GPIO.setup(24, GPIO.OUT, initial=False) #Siren pin setup
try:
GPIO.wait_for_edge(23, GPIO.RISING)
print "\nRising edge ALARM"
sendemail(from_addr = '@gmail.com',
to_addr_list = ['@gmail.coml'],
cc_addr_list = [''],
subject = 'ALARM',
message = 'alarm',
login = '@gmail.com',
password = '****')
GPIutput(24, True)
time.sleep(5)
except KeyboardInterrupt:
GPIO.cleanup() # clean up GPIO on CTRL+C exit
GPIO.cleanup() # clean up GPIO on normal exit