ad1938 cracking

Hello VTFC,

Please take this in the spirt of me trying to help. I see in your profile that you are a student so I will take a few extra minutes to type out a bit more.

There are MANY things that can cause some of the symptoms you have reported so I need a lot more information. It is almost like you report that you cannot drive your car down the road. What is wrong?... Well, I would need a little more info, it could be your key battery is dead so you cannot get into the car. It could be a dead battery, it could be no air in the tires. It could be no gas in the car. The transmission could be damaged and non-functional. You get the point...

In your case I think you may have two problems. The crackles and the overtones. They most likely are related in that it is most likely data transmission issues but it could be two different causes.

For the crackles. There are many things that can cause this. Need a lot more info and this info can also help for both problems.

1) What is your master clock setup for your system? Your entire system. Where is it produced and where does it go to?

2) Which part is the clock master for bit clock and LRCLK?

3) What is your sample rate?

4) That hardware are you using? Your own design or several eval boards?

If you are using eval board then how are you connecting them together? Detail the connections and take some pictures? If you are using jumper wires, also called fly-wires, this could be a cause of these crackles.

5) what are the register settings for the codec?

6) What are the register settings for the DSP? In this case supply the SigmaStudio schematic so all the info is there.

I think that is enough for now.

Thanks!

Dave T