Text missing in iReport preview or exporting

Hi everyone, I’m stuck in a problem and hope anyone could help me. I’m designing a report with iReport(last version), which I have a long text dynamically received by parameter. The problem is that there are text missing at the end of each page (variably amounts of lines missing in every page). I have  found a lot of similar questions but none of them could help me since they got this problem only when exporting to pdf or another format, and I am having this situation with all formats exporting and even with the internal iReport previewer, which happens the same thing and if I keep scrolling down and up the page, some lines does appear or miss again!
I have tried font extensions and changing environment, but nothing has changed.

This is how the textField is setted up:

            <textField isStretchWithOverflow="true">
                <reportElement uuid="e97e546b-ad36-44e7-bccf-52e2ff6a20a7" stretchType="RelativeToBandHeight" x="15" y="223" width="524" height="23" isPrintWhenDetailOverflows="true"/>
                <textElement>
                    <font fontName="Times New Roman" size="9" pdfEncoding="Cp1250" isPdfEmbedded="true"/>
                </textElement>
                <textFieldExpression><![CDATA[$P{corpo}]]></textFieldExpression>
            </textField>

Any help will be really apreciated. Thanks in advance.