Call is disconnected after being transferred by the AA SPA 400

Question

I have 2 groups set up in the AA to transfer to different groups ie "Accounts" or "Production". These all worked originally, but now they seem to have stopped working. Callers dial in and press "13" as per the prompts, then the AA message tells them to wait while the call is transferred, and then the call is disconnected.
This only happens for one of the prompts, the other one is fine. As i said this all worked fine originall, and no settings have been changed.....
Any ideas / help / suggestions greatly appreciated.
System is SPA9000, SPA400, SPA942 x 3

Answer 1

After having searched through this and a number of other forums I am amazed that no one has come across and understands the true reason this is happening.  The other posts do offer some insight and good suggestions but no one has realized the true underlying problem.  Apparently the AA, no mater what dial plan you use, will forward any partially dialed portion of the numbers that match the list.  So even if you specifically limit the acceptable numbers to only the extensions on your system you can still get a partial result passed on from the AA which does not have a valid extension on your system.
For Example:
DP1 = (120|102|103|152|100|9|<0:100>|<*8:vmm4>)
AA Script 1 =
<aa>
<form id="dt" type="menu"><audio src="prompt5" bargein="T"/><noinput timeout="5" repeat="T"/><dialplan src="dp1"/>
<nomatch repeat="F"><audio src="prompt3" bargein="T"/></nomatch>
<match><case input="9"><audio src="prompt8" bargein="F"/></case>
<default><audio src="prompt2"/><xfer name="ext" target="$input"/></default>
</match>
</form>
</aa>
You would think this would be sufficient to limit inbound calls to just the extensions listed in the dial plan.  Not so.  The caller can dial any part of the listed extensions (1,10,12,15,*...) and the call will still be transferred and subsequently dropped.  I tried every possible combination of dial plan settings including specifically rejecting (which you should not have to do) everything other then the desired combinations.  Problem is if you try to reject any subset of the valid combinations it interferes with them and they get rejected to.  The real problem here is in that how the dial plan is being processed allows these invalid partial number through.  Believe it or not this happens more then you think.  For whatever reason a digit is not heard or does not get registered will cause this to happen.  Adjusting the DTMF settings does improve things in most cases but does not solve the issue.  Problem is that any number passed on by the AA that does not translate to a valid destination will get dropped.
After much trial and tribulation I have come up with a way using the AA script to eliminate any and all none desired digit combinations to prevent anything from getting transferred by the AA that will get dropped.  It is a work around but it is effective and reliable.  Solution is simple.  Use the AA script to take specific action on only the desired responses.  Everything else goes to the default which could play an "invalid..." message or other action.  Here's how it looks:
DP1    =    (0S0|*8S0|xxxS0)
AA Script 1 =
<aa>
<form id="aadpw" type="menu"><audio src="prompt5" bargein="T"/><noinput timeout="5" repeat="T"/><dialplan src="dp1"/>
<nomatch repeat="F"><audio src="prompt3" bargein="T"/></nomatch>
<match>
<case input="*8"><audio src="prompt2"/><xfer name="ext" target="vmm4"/></case>
<case input="0"><audio src="prompt2"/><xfer name="ext" target="100"/></case>
<case input="100"><audio src="prompt2"/><xfer name="ext" target="$input"/></case>
<case input="102"><audio src="prompt2"/><xfer name="ext" target="$input"/></case>
<case input="103"><audio src="prompt2"/><xfer name="ext" target="$input"/></case>
<case input="120"><audio src="prompt2"/><xfer name="ext" target="$input"/></case>
<case input="152"><audio src="prompt2"/><xfer name="ext" target="$input"/></case>
<default><audio src="prompt3" bargein="T"/></default>
</match>
</form>
</aa>
It is a little like using a sledge hammer to pound in a tack but it works.  It's the only thing I was able to come up with that does.  Oh, and by the way you may notice the case for "*8".  This allows transfer from and outside line to the voice mail manager ("vmm4") on line 4.  You can modify the dial plan and AA script for any sequence you want.  The case for "0" is there to allow outside callers to press "0" and get transferred to whatever valid extension or hunt group you wish to designate.
Hope this offers a little more insight into what was really happening.  Let me know if anyone comes up with a better way to do this.