After several years of steadily improving results, Crowe Horwath saw an increase in adverse findings in its latest regulatory inspection.

The Public Company Accounting Oversight Board says it scrutinized portions of 15 different audit files at Crowe Horwath during its 2016 inspection and found problems in five of them for a 33-percent rate of deficiency. In its 2015 inspection of the same firm, the board noted problems with only 3 of 14 audits, or 21 percent. That was a low for the firm itself, and it was a low among the eight largest audit networks in 2015.

The PCAOB’s report on Crowe is the first the board has published for the leading audit firms from its 2016 inspection cycle. During that year, the board reviewed audit work on 2015 financial statements and internal control over financial reporting.

The PCAOB’s chief inspector said following the 2016 inspection cycle that the board found an overall reduction in adverse findings that year, but a spike at one Big 4 firm. The board recently indicated it saw yet another year of overall improvement in its 2017 inspections, although it’s still not satisfied with the overall number of deficiencies. Given the time the board spends in drafting and reviewing inspection reports, those individual firm inspection reports won’t likely be available until well into 2018.

At Crowe, the board said all five of the faulty audits studied in 2016 exhibited problems with the audit of internal control, but only two of the five also contained errors in the audit of financial statements. The firm had the greatest difficulty with testing the design or operating effectiveness of controls selected for testing and with checking the accuracy and completeness of reports or data produced by the issuer. Those have been common pain points for auditors in PCAOB inspections for the past few years.

The PCAOB’s report says the firm made 20 different mistakes in the audit of internal control across the five problematic audits. Inspectors called out three specific errors in responding to risks of material statement and three errors in audit sampling. The report flags only one mishap in complying with auditing standards around the audit of accounting estimates, which historically has been a common trouble spot for many firms.

In a letter attached to the report, Crowe Horwath says it has taken action in accordance with standards and firm policies to address each of the concerns raised in the inspection. “While we are pleased with the overall trend of improvement in our inspection results over the past several years, we are not content with the level of deficiencies in the 2016 report,” said Mark Baer, managing partner at Crowe Horwath, in a statement. “We will continue to use this constructive feedback to enhance our audit processes, procedures and training.”