Well, PCAP's are usefull, but despite of it, it's hard to understand the issue as I can't listen what you hear during the call progress. The following text assume I understanded the issue correctly.
The 71cisco-fail.pcap show that phone has sent INVITE, the Asterisk responded 183 Session Progress and some inband voice message has been sent to phone. After 0.3s another response, 181 Call is being forwarded, arrived from Asterisk. Followed by 180 RINGING message.
Well, now, you should hear the locally generated ring back tone - not a message from exchange.
It has ben ordered by 180 Ringing message. If you wish to hear a message here, 183 Session Progress message needs to be sent from exchange. That's the difference between 180 and 183 message. The first mean that ringback tone should be generated locally by device, the second mean that progress tone will be sent inband from remote side and local device should play them to the user.
So, it seems that configuration of your Asterisk is wrong.
You can try to set "Sticky 183" configuration option (of SPA phone) to yes.
It's option dedicated to solve interoperability problem misconfigured exchanges like your's. According XLite client - it seems it has simmilar configuration set to "yes" already (or it's not configrable and it is internal default).
But even it will help, it doesn't mean that the Asterisk is not misconfigured. Problems with others SIP clients connected to it are immitent. And not all clients can be configured accordingly to cope with such misconfigured exchange. So the only final solution is to correct Asterisk's configuration.
Of course, if I didn't understood the issue correctly, the conclusions above may be wrong from scratch.
