yes, a CA can be partner in two firms at d same time but subject to ceiling on limit of no. of auit.
According to sec 224(1B) of Companies Act, 1956, a person can be appointed as an auditor, who is not in full employment elsewhere or u can say auditor in two more than two firms can conduct maximum of audit of 20 companies subject to sub ceiling of 10 for companies having paid up capital of Rs. 25 Lacs or more.
But dis rule applies only to Public Companies. an auditor can conduct any no. of audits for private companies.
no ceiling for private companies.