[signal34]

The problem is this:

On the stock rom, the registry setting for a crucial phone function is incorrect. If you navigate to HKLM\Comm\ConnMgr\Planner\Settings, you will see the value name SuspendResume entry is MULTI_SZ, which is wrong (value data is #777).

Delete this entry, create a new REG_SZ value with a value name of SuspendResume and a value data of #777. Soft reset, and there is no need to disable the stock dialer anymore, and rings come through as they should.