Record no longer recognizing silence after upgrading

upgraded from asterisk 1.4 to and my record calls no longer recognize silence to end the recording, it just keeps recording until the timeout is hit. Using a simple little context to test in both 1.4 and 1.6:

exten => _X.,1,NoOp(Startcall beginning)
exten => _X.,n,Record(/tmp/testfile.wav,3,30)
exten => _x.,n,NoOp(Finished recording)
exten =>_x.,n,Hangup()

works great in 1.4, but not 1.6, so i’m guessing something changed in conf files maybe? 1.6 doesn’t report any warnings or errors, even with verbosity turned up, it just seems to ignore the silence parameter now.

Here’s the CLI output from 1.4:
– Executing [222@startcalltest:1] NoOp(“SIP/testuser1-00000002”, “Startcall beginning”) in new stack
– Executing [222@startcalltest:2] Record(“SIP/testuser1-00000002”, “/tmp/testfile.wav,3,30”) in new stack
– <SIP/testuser1-00000002> Playing ‘beep.gsm’ (language ‘en’)
– Executing [222@startcalltest:3] NoOp(“SIP/testuser1-00000002”, “Finished recording”) in new stack
– Executing [222@startcalltest:4] Hangup(“SIP/testuser1-00000002”, “”) in new stack

And the CLI output from 1.6 that doesn’t seem to recognize silence, looks identical to me:
[Nov 1 13:11:08] – Executing [123@startcalltest:1] NoOp(“SIP/testuser1-00000000”, “Startcall beginning”) in new stack
[Nov 1 13:11:08] – Executing [123@startcalltest:2] Record(“SIP/testuser1-00000000”, “/tmp/testfile.wav,3,30”) in new stack
[Nov 1 13:11:08] – <SIP/testuser1-00000000> Playing ‘beep.gsm’ (language ‘en’)
[Nov 1 13:11:40] – Executing [123@startcalltest:3] NoOp(“SIP/testuser1-00000000”, “Finished recording”) in new stack
[Nov 1 13:11:40] – Executing [123@startcalltest:4] Hangup(“SIP/testuser1-00000000”, “”) in new stack

Anyone have ideas on why this might be happening?