SPDIF on Win 7—stuttered, perfect via exclusive mode for 3 d, now none, Was: Windows 7 Optical Output Problem (TOS #6) Options

[Lucian23]

Hello everybody!
I am running genuine Windows 7 Professional 32-bit and have installed K-Lite Mega Codec Pack 6.7.0. I am using Media Player Classic - Home Cinema 1.4.2803.0 for watching HD movies with Dolby Digital (DD) and Digital Theater System (DTS) formats.
My sound card is a Creative Sound Blaster X-FI XtremeGamer and my audio system Logitech Z-5500 Digital 5.1 Speaker System.
I have the latest driver installed for Windows 7 from Creative website 2.18.0015.
I couldn't get a clear, crisp sound through SPDIF; sound stucks like it was a bad CD that hangs over and over again; sometimes (very strange, happened only 2 times) the Power button from Logitech System fade away for a few seconds then comes back and the sound interrupts and crackle.
Eventually I managed to get PERFECT sound through SPDIF ticking only "Allow applications to take exclusive control of this device" from the Advanced tab of SPDIF Out Properties, but ONLY for 3 days.
My PROBLEM is that (no matter what settings I have) suddenly I have NO SOUND AT ALL through SPDIF !!!
I use AC3 filter for SPDIF passthrough and the Logitech Digital SoundTouch™ control center shows "No Digital Data".
I would also like to mention that on Windows XP I had NO PROBLEM.
I want from now on to have Windows 7 on my computer but also to be able to listen DD & DTS audio formats.
Can someone help me, PLEASE?

Thank you in advance,


Lucian23