Apparently, you cannot control anything on the other computer if this computer does not run some process which communicates on the network and obeys your commands.
First of all, you need to control audio on a local computer. One of the ready-to-use libraries to do it with .NET is NAudio:
http://naudio.codeplex.com/[
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Now, you need to create an application which could listen to a network connection (that is, to act as a server part of a network application does), accepts connection and received and sends data, so the received data could be control commands. This can be done on one of several different levels of networking, remoting or WCF.
Please see my overview of these approaches in my past solutions:
how i can send byte[] to other pc[
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Communication b/w two Windows applications on LAN.[
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The most adequate form for such network application is the Windows Service:
http://en.wikipedia.org/wiki/Windows_Service[
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http://technet.microsoft.com/en-us/library/cc783643%28v=ws.10%29.aspx[
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http://msdn.microsoft.com/en-us/library/ms685141.aspx[
^].
To develop a Windows Service with .NET, start here:
http://msdn.microsoft.com/en-us/library/zt39148a.aspx[
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There CodeProject articles could be helpful:
Windows services Error[
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Configure Windows Service with UI[
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That's all which is involved. There can be many advanced featured you would need to consider, authentication, and so on.
—SA