well i cant really pinpoint where the problem may be, we use sulptura ata and grandstream 2000 devices. all registers perfectly, all are bound to media server and unchecked support for re-invite in the voip gateway config (else music on hold is buggered)
If the receptionist dials an extension, she hears ringing when the other side picked up the line. The other line hears nothing.
part of server log:
Time Function Message
12:04:05.578 ListenConnect [CM114000] SL: connected viop-srv-01:0/PHPExtension_0 at [viop-srv-01:0]/PHPExtension_0
11:15:06.937 StratLink:

nHangUp [CM104001] Call(18): Ln:10001@Voiceworks Notom hung up call; cause: BYE; from IP:213.239.164.175
11:14:50.812 MediaServerReporting:

TMFhandler [MS211000] Call(18) Ln:10001@Voiceworks Notom: DTMF (in-band) from 213.239.164.176:10186 detected.
11:10:53.125 MediaServerReporting:

TMFhandler [MS211000] Call(20) Ext.770: DTMF (in-band) from 10.10.1.44:16406 detected.
11:03:01.328 StratLink:

nHangUp [CM104001] Call(21): Ln:10001@Voiceworks Notom hung up call; cause: BYE; from IP:213.239.164.175
11:02:45.140 MediaServerReporting::RTPSender [MS004000] Call(21) Ext.110: (ACTIVE): Can't send RTP stream to 0.0.0.0:5004 destination unreachable
11:02:42.953 CallLegImpl:

nConnected [CM103001] Call(21): Created audio channel for Ext.110 (10.10.1.41:5004) with Media Server (10.10.1.12:7062)
11:02:42.937 StratInOut:

nConnected [CM104005] Call(21): Setup completed for call from Ln:10001@Voiceworks Notom to Ext.110
11:02:42.937 CallLegImpl:

nConnected [CM103001] Call(21): Created audio channel for Ln:10001@Voiceworks Notom (213.239.164.176:17512) with Media Server (84.107.147.253:9002)
11:02:40.718 CallConf:

nProvisional [CM103003] Call(21): Ext.110 is ringing
11:02:40.593 CallConf:

nIncoming [CM103002] Call(21): Incoming call from 0652036146 (Ln:10001@Voiceworks Notom) to sip:
[email protected]:5080
11:02:32.750 StratLink:

nHangUp [CM004001] Call(18): HangUp from wrong leg has arrived. Leg will be removed from call
11:02:25.656 CallLegImpl:

nConnected [CM103001] Call(18): Created audio channel for Ext.770 (10.10.1.44:16406) with Media Server (10.10.1.12:7058)
11:02:25.656 StratTransfer::finishTransfer [CM108005] Call(18): Transfer finished, Ln:10001@Voiceworks Notom is connected to Ext.770
11:02:25.656 StratTransfer:

nConnected [CM008008] Call(18): Transfer: wrong leg is connected
11:02:25.625 StratLink::Transfer [CM104002] Call(18): transfers Ln:10001@Voiceworks Notom from Ext.110 to sip:
[email protected]
11:02:21.437 CallLegImpl:

nConnected [CM103001] Call(20): Created audio channel for Ext.770 (10.10.1.44:16406) with Media Server (10.10.1.12:7058)
11:02:21.421 StratInOut:

nConnected [CM104005] Call(20): Setup completed for call from Ext.110 to Ext.770
11:02:21.421 CallLegImpl:

nConnected [CM103001] Call(20): Created audio channel for Ext.110 (10.10.1.41:5006) with Media Server (10.10.1.12:7056)
11:02:08.765 CallConf:

nProvisional [CM103003] Call(20): Ext.770 is ringing
11:02:08.656 CallConf:

nIncoming [CM103002] Call(20): Incoming call from 110 (Ext.110) to sip:
[email protected]
11:02:06.515 MediaServerReporting::RTPSender [MS004000] Call(18) Ext.110: (ACTIVE): Can't send RTP stream to 0.0.0.0:5004 destination unreachable
11:01:35.609 MediaServerReporting::RTPSender [MS104000] Call(18) Ext.110: (ACTIVE) RTP stream to 10.10.1.41:5004 restored.
11:01:35.578 StratInOut:

nHangUp [CM104007] Call(19): Call from Ext.110 to 110 has been terminated by Ext.110; cause: CANCEL; from IP:10.10.1.41
11:01:16.156 CallConf:

nProvisional [CM103003] Call(19): Ext.770 is ringing
11:01:16.031 CallConf:

nIncoming [CM103002] Call(19): Incoming call from 110 (Ext.110) to sip:
[email protected]
11:01:13.171 MediaServerReporting::RTPSender [MS004000] Call(18) Ext.110: (ACTIVE): Can't send RTP stream to 0.0.0.0:5004 destination unreachable
11:00:18.484 CallLegImpl:

nConnected [CM103001] Call(18): Created audio channel for Ext.110 (10.10.1.41:5004) with Media Server (10.10.1.12:7048)
11:00:18.453 StratInOut:

nConnected [CM104005] Call(18): Setup completed for call from Ln:10001@Voiceworks Notom to Ext.110
11:00:18.453 CallLegImpl:

nConnected [CM103001] Call(18): Created audio channel for Ln:10001@Voiceworks Notom (213.239.164.176:10186) with Media Server (84.107.147.253:9000)
11:00:15.437 CallConf:

nProvisional [CM103003] Call(18): Ext.110 is ringing
11:00:15.328 CallConf:

nIncoming [CM103002] Call(18): Incoming call from 0646005458 (Ln:10001@Voiceworks Notom) to sip:
[email protected]:5080
10:58:09.218 StratLink:

nHangUp [CM104001] Call(17): Ln:10000@Gorree Voiceworks hung up call; cause: BYE; from IP:213.239.164.175
10:56:17.218 CallLegImpl:

nConnected [CM103001] Call(17): Created audio channel for Ext.740 (10.10.1.50:16416) with Media Server (10.10.1.12:7046)
10:56:17.187 StratInOut:

nConnected [CM104005] Call(17): Setup completed for call from Ln:10000@Gorree Voiceworks to Ext.740
10:56:17.171 CallLegImpl:

nConnected [CM103001] Call(17): Created audio channel for Ln:10000@Gorree Voiceworks (213.239.164.176:15240) with Media Server (84.107.147.253:9002)
10:56:02.375 CallConf:

nProvisional [CM103003] Call(17): Ext.740 is ringing
10:56:02.234 CallConf:

nIncoming [CM103002] Call(17): Incoming call from 0 (Ln:10000@Gorree Voiceworks) to sip:
[email protected]:5080
10:51:36.125 StratLink:

nHangUp [CM104001] Call(16): Ln:10001@Voiceworks Notom hung up call; cause: BYE; from IP:213.239.164.175
10:48:29.218 CallLegImpl:

nConnected [CM103001] Call(16): Created audio channel for Ext.110 (10.10.1.41:5004) with Media Server (10.10.1.12:7044)
10:48:29.171 StratInOut:

nConnected [CM104005] Call(16): Setup completed for call from Ln:10001@Voiceworks Notom to Ext.110
10:48:29.171 CallLegImpl:

nConnected [CM103001] Call(16): Created audio channel for Ln:10001@Voiceworks Notom (213.239.164.176:15994) with Media Server (84.107.147.253:9000)
10:48:20.562 CallConf:

nProvisional [CM103003] Call(16): Ext.110 is ringing