The claimant appeals from a decision of the Unemployment Insurance Appeal *935Board which denied benefits because of his voluntarily leaving his employment without good cause. After hearings, at which the claimant refused to testify, the Referee found that “ Claimant’s insubordinate attitude towards his superior led to the termination of his employment. Claimant should have been aware that his insubordination would cause the termination of his employment.” What constitutes good cause within subdivision 1 of section 593 of the Labor Law regarding disqualification for unemployment compensation in cases of voluntary separation is a question of fact (Matter of Sperling [Cathermood], 20 A D 2d 584, mot. for iv. to opp. den. 14 N Y 2d 481). The resolution of factual issues is within the province of the board if supported by substantial evidence (Labor Law, § 623; Matter of Jacobson [Cathcru:ooci], 20 A D 2d 733). On the present record we are without authority to disturb the board’s determination. We find no justification for the claimant’s failure to testify based upon his complaint that the employer did not produce the claimant’s personnel file. There is no showing in this record that the file, or its contents, was pertinent to the issue resolved by the Referee and affirmed by the board. Decision affirmed, without costs. Gibson, P. J., Reynolds, Aulisi and Hamm, JJ., concur.