Not being a laptop owner I might be talking nonsenses here LOL. However if possible try disabling both webcams for a while and listen to the sound quality. This will help define the issue perhaps. Then enable just one, disable it and enable the other. A pain of course but if it helps pinpoint the issue it might be worth the effort. We find with Skype it is great but on the odd occasion a webcam will affect the speech causing garble chatting. Closing the webcams seems to fix it. Generally this is the same people each time - and of course the problem MUST be on our computers because they tell us so. On the issue of echo we have not had that when talking to people with built in mics on laptops. On a desktop with a standalone mic in front of the speakers it can become bedlam

telling us your version of windows would be helpful try this method and see if it works. How to uninstall Windows Live Messenger

7-Zip 9.20 Adobe Flash Player 11 ActiveX Adobe Reader XI (11.0.01) AutoCAD 2010 - English AutoCAD 2010 - English CCleaner Conexant HD Audio D3DX10 ESET Online Scanner v3 Google Chrome Google Drive Google Update Helper HDAUDIO Soft Data Fax Modem with SmartCP HP Quick Launch Buttons Junk Mail filter update LogMeIn Malwarebytes Anti-Malware version 1.70.0.1100 Mesh Runtime Messenger Companion Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office 2007 Service Pack 3 (SP3) Microsoft Office Basic 2007 Microsoft Office Basic 2007 Microsoft Office Excel MUI (English) 2007 Microsoft Office File Validation Add-In Microsoft Office Outlook MUI (English) 2007 Microsoft Office Proof (English) 2007 Microsoft Office Proof (French) 2007 Microsoft Office Proof (Spanish) 2007 Microsoft Office Proofing (English) 2007 Microsoft Office Proofing Tools 2007 Service Pack 3 (SP3) Microsoft Office Proofing Tools 2007 Service Pack 3 (SP3) Microsoft Office Proofing Tools 2007 Service Pack 3 (SP3) Microsoft Office Shared MUI (English) 2007 Microsoft Office Shared Setup Metadata MUI (English) 2007 Microsoft Office Word MUI (English) 2007 Microsoft Security Client Microsoft Security Essentials Microsoft Silverlight Microsoft SQL Server 2005 Compact Edition [ENU] Microsoft Visual C++ 2005 Redistributable Microsoft Visual C++ 2008 Redistributable - x86 9.0.30729.17 Microsoft Visual C++ 2008 Redistributable - x86 9.0.30729.6161 MSVCRT NVIDIA Drivers Optimum App for Laptop 1.62 PartyPoker QLBCASL Security Update for Microsoft Office 2007 suites (KB2596615) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596672) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596744) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596754) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596785) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596792) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2596871) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2597969) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2687311) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2687441) 32-Bit Edition Security Update for Microsoft Office 2007 suites (KB2687499) 32-Bit Edition Security Update for Microsoft Office Excel 2007 (KB2687307) 32-Bit Edition Security Update for Microsoft Office InfoPath 2007 (KB2687440) 32-Bit Edition Security Update for Microsoft Office Word 2007 (KB2760421) 32-Bit Edition Spybot - Search & Destroy SUPERAntiSpyware Synaptics Pointing Device Driver Update for 2007 Microsoft Office System (KB967642) Update for Microsoft Office 2007 Help for Common Features (KB963673) Update for Microsoft Office 2007 suites (KB2596660) 32-Bit Edition Update for Microsoft Office 2007 suites (KB2596848) 32-Bit Edition Update for Microsoft Office Excel 2007 Help (KB963678) Update for Microsoft Office Outlook 2007 (KB2687404) 32-Bit Edition Update for Microsoft Office Outlook 2007 (KB2687404) 32-Bit Edition Update for Microsoft Office Outlook 2007 Help (KB963677) Update for Microsoft Office Outlook 2007 Junk Email Filter (KB2760586) 32-Bit Edition Update for Microsoft Office Script Editor Help (KB963671) Update for Microsoft Office Word 2007 Help (KB963665) VNC Mirror Driver 1.8.0 VNC Printer Driver 1.8.0 VNC Server 5.0.3 VNC Viewer 5.0.3 Windows Live Communications Platform Windows Live Essentials Windows Live Essentials Windows Live Family Safety Windows Live Family Safety Windows Live ID Sign-in Assistant Windows Live Installer Windows Live Mail Windows Live Mail Windows Live Mesh Windows Live Mesh Windows Live Mesh ActiveX Control for Remote Connections Windows Live Messenger Windows Live Messenger Windows Live Messenger Companion Core Windows Live MIME IFilter Windows Live Movie Maker Windows Live Movie Maker Windows Live Photo Common Windows Live Photo Common Windows Live Photo Gallery Windows Live Photo Gallery Windows Live PIMT Platform Windows Live Remote Client Windows Live Remote Client Resources Windows Live Remote Service Windows Live Remote Service Resources Windows Live SOXE Windows Live SOXE Definitions Windows Live UX Platform Windows Live UX Platform Language Pack Windows Live Writer Windows Live Writer Windows Live Writer Windows Live Writer Resources

Does anybody have a clue what might be causing this? Sounds like the backlight is bad, it's a little lamp that's located in the lower backside of the screen that lights up the screen. Search google for lcd backlight to learn more. There is another component that could be a problem, but the name escapes me now. Good thing you don't have dead pixel lines, that would mean a screen replacement, very expensive. Good thing you have the extended warranty.