Laptop Internal Mic Noise issue

Are you playing back through speakers? Could be feedback.

If you import an audio file and play it (no recording involved), does it sound the same? My hunch is that it does and this is related to the driver mode you are using. WDM/KS (or even MME) driver modes have been the only modes I can get playback with SONAR on a stock laptop. The audio buffer often also has a sweet spot where too high/too low will cause distortion (what you are hearing). Arming/Input echoing will engage the "playback" portion noted above, which most likely needs adjusting. These links are for X3, but will be similar for you:
 
Open SONAR Preferences:

1. Check the driver mode at the top of "Preferences->Audio->Playback and Recording" preferences (WDM/KS first, then MME if these steps fail). You should have the audio profiler pop up to analyze your machine when you change this.
2. Then check Audio->Devices to make sure devices are selected.
3. Lastly, the Audio->Driver Settings (one that has the "sweet spot"). To be safe, I would start with Audio Driver Bit Depth of 16, and the Buffer Size slider about 1/3 the way up.
4. Check playback of an audio file, if fine you can revisit Step 3 and knock down buffer in small increments until the audio distorts, then move it back up a notch.
5. If WDM/KS collapses completely, try MME mode per the above.

 
That said, for audio recording you will most likely find these settings lackluster, and may be forced into 16-bit recording with latency (delay) so bad that you might need to mute a track being recorded so it doesn't throw you off-kilter (i.e., you will not be able to monitor the signal the DAW is recording).
 
For any recording functions, you are best to look into a dedicated audio interface with ASIO drivers specific to the device (which will also give you better playback performance).