Disqualification under Sec.226(3)(d): a person who is indebted to the company for an amount exceeding one thousand rupees, or who has given any guarantee or provided any security in connection with the indebtedness of any third person to the company for an amount exceeding one thousand rupees;
Where the firm is indebted to the company, each and every partner is also deemed to have been indebted and vice versa.
Hence, the individual person will be disqualified to act as auditor.