The sound may not be heard from the external monitor's speaker which is connected to the DisplayPort-HDMI converter (Dongle). Some dongles do not work with audio, but others work with no problem.
Any of the following ThinkPad discrete graphics model systems running Windows 7 (32-bit, 64-bit) may be affected by this symptom:
- T410, T410i, T410s
- T510, T510i
- W510, W701, W701ds
Use the dongles listed below that Lenovo has tested with the above systems.
Lenovo recommended dongles