Audiorecord is blocking voice during phone call in Nexus one

Question

I am using audiorecord to get micrphone data in a background service on android. During the time when the code is running, if I make a phone call on nexus one then the receiver cannot hear what I am saying.

I tested the same code on Motorola Droid. Surprisingly, in Droid the receiver can hear what I can saying.

My initialization looks like the following:

aRecorder = new AudioRecord(android.media.MediaRecorder.AudioSource.MIC, 8000, AudioFormat.CHANNEL_CONFIGURATION_MONO,
 AudioFormat.ENCODING_PCM_16BIT)