Professional misconduct

Every learned profession have a professional dignity and integrity.  It is the duty of each members of the profession to maintain these things of the profession.  So the chartered Accountant is also a learned professional and it is his duty to maintain its intergrity and reputation with his conduct.  So any act of the members which are against this principle is a misconduct.  Simply saying when a member undertake any   misconduct by not doing an activity which he is professionally bound to do it may be termed as Professional Misconduct and the rest is other misconduct.

Professional misconduct means act of not doing things which a professional is bound to do

whereas 

Code of Conduct means set of rules and regulations one must observe while discharing his duties, failing of which would lead to professional misconduct.