A similar story to a few other posts. Very low volume outgoing using the internal Mic in a Skype call.
- Brand new XPS15 9530
- Immediate upgrade to Win 10
- Windows update and Dell updates applied and up to date
- Audio drivers show Realtek HD Audio, 6.0.1.7544
- Skype 7.10.0.101 up to date.
Skype microphone showing very low volume even with all settings to max (+30db, 100%). Calls to Test Call return nothing or very quiet voice. Control panel, Sounds, Recording shows almost no movement in the display unless you shout or tap the Mic area above the screen. Playing with all the various enhancement options both in Control panel, Sounds, Recording and Dell Audio don't seem to have any effect. However I think I've seen "Listen to this device" and Voice Recorder work fine.
A possible temporary fix is to go to Control Panel, Device manager, Sound Video and Games controllers, Update Driver, Browse, Pick and choose the generic High Definition Audio Device. This is not really a long term solution but does seem to work correctly.
I'm not certain yet whether the problem is Dell hardware, Windows 10, Skype or the Realtek drivers. But more or less out of the box the combination seems to be currently broken and unusable. Please investigate and find a fix. It should not be hard to duplicate the problem.