Cirrus Logic Design Verification Engineer - Mixed Signal Audio Codecs interview questions

1st round - phone interview - questions below 2nd round phone after 3 weeks- take-home assignment where design specs were given and asked to design and verify. 3rd after 2 weeks - on site interview Very bad experience as the interviewers were themselves inadequately prepared to handle the interview. The day started with the first interviewer sending another person instead. Their head of the division seemed to slight my previous work. The prospective immediate manager was not friendly. Never once did he smile/greet me during the entire process even though I tried to greet him on multiple occasions- may be he is already not interested in interviewing me for the position. Other interviewers were friendly and the questions were pretty basic. Those rounds felt like a good discussion. In one round, the interviewers themselves were unable to assess my solution during the interview as they "have been out of touch with the problem" that they asked me to solve - shows a lack of respect for my time and effort. I wouldn't ask a question that I don't know a definite answer to. My impression has been that they already had a candidate selected and they did the interview just for the sake of it (Or was I being used as a test subject for their "innovative" interview techniques that they still haven't mastered? Or was it a special treatment since I was from a particular employer?) What a waste of my time and effort!