| Pin | Pin Name | Description |
| 1 | control | +2.4v |
| 2 | Audio channel | left or right |
| 3 | Audio channel | left or right |
| 4 | Ground | Ground |
Ring 1 has a 1.4K ohm loading to Ground. When talk/play/pause function button is pushed it applies a short across ring 1 and 4. With ring 1 disconnected the Pearl plays via its internal speaker. However with 1 and 4 shorted it continues to play from its internal speaker!