Synch - Sonar 8.5 (Audio)

Hey, dont mean to conjure up topics that have probably been beaten to death but after doing some searching on "audio-midi synch" I still cant find a solution.

PROBLEM - When playing back recorded audio (whether it's guitar or bass) the timing is off.  

The timing is either off right at the start of the song OR it stays in rhythm but tapers off toward the end.  For example, if I do a quick 1-2 minute song, usually there's no problem; if it's 3-4 minutes I have to split clips and go into the Clip Properties to change the START time so it plays in synch with the midi drums (Session Drummer).  
I've changed the Playback/Record buffer sizes from 64 to 128 to 256 but it doesn't seem to work.  I've also updated the drivers for the Lambda sound card (which I assume is not highly recommended for Sonar).    

I'm wasting a lot of time messin' with audio clips. 

Appreciate anybody's help.


HP Pavilion DV4
O/S - Vista (unfortunately)
Processor - AMD Turion 2.1 Ghz
4G Memory (64-bit)
 
Sonar 8.5 Producer
Sound Card - Lexicon Lambda
 
Audio Options
Buffers in Playback Queue - 2
Buffer Size - 10.0 sec (441 Samples)
Driver Mode - WDM/KS
Dithering - Triangular

Hey, thanks for the response.

It's showing "1: USB Audio Device" (the audio bit is 16 with "64-bit Double Precision Engine" checked, in case ya needed to know).

Yeah, not sure why it wouldn't show Lambda in these two fields.  In Control Panel - Sounds it shows Lambda only on the Recording tab; for Playback it just states 4-USB Audio Device.

What's funny is that I changed the driver mode to ASIO and when I re-opened Sonar and tried to open the Audio, it gave me a fatal error.  It actually wouldn't allow me to go back into the AUDIO folder.  I finally unplugged the sound card and re-started the computer, then changed it back to WMD.
WTF?

Yeah I just downloaded them.  Any other clues?  

Appreciate your help.

Hey, thanks for the response.  I did download the Vista drivers so were set there.

Ok, now how do I make sure there are no conflicts with the computer's on-board sound card?  I went into Control Panel - Sounds/Hardware and made sure the Lexicon Lambda is selected as default but I assume there's somewhere else I should check??

At the bottom of the Sonar screen it's showing 44.1 / 16 bit.

You mentioned ASIO - I'm using WDM.  When I select ASIO, I get a fatal error (??).

Actually I just checked it out and yes, it says ASIO drivers.  But I've been using it fine for like two years now.  I'll reinstall and see what happens.

But what about the errors I'm getting when I select ASIO in Sonar?  Any ideas?

Really appreciate your feedback.

Thanks Bill.  Yes, I checked that too.

SOLVED - Basically what happened was the old audio, recorded at different buffers and play/read caches was conflicting with the new audio.  So, I had to DELETE basically all the audio and re-record.  F was that a pain in the ass but soooooo worth it.  

Appreciate everybody's help.

Thanks.