Hi Jamie
We bought new Challenger in Jan this year we had problem with our alarm going off all the time, we got in touch with swift and they told us they have had some probelms with the units, so it might be worth your while contacting them, we then had to take our caravan back to the dealers we bought it from to get the alarm unit replaced. It didn't buz it just kept going off when we tried to set it in the storage.
Hope this helps.
Dave