(Reuters) -Super Micro Computer ( SMCI ) shares slumped 23% premarket on Wednesday after it said Ernst & Young had resigned as its public accounting firm, over a month after Hindenburg Research alleged "accounting manipulation" at the AI server maker.

The company said EY in late July communicated to Super Micro's auditing committee several matters relating to transparency and completeness of communications with the accounting firm.

It has begun the process of identifying a new independent registered public accounting firm.

The accounting firm's resignation is the latest of Super Micro's woes.

A day after short-seller Hindenburg's report, the company delayed the filing of its annual report, citing a need to assess "its internal controls over financial reporting".

In late September, the Wall Street Journal reported that the U.S. Department of Justice was investigating the company.