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    <link:label id="lab_ck0001027596_S000110367Member_documentation_en-US" xlink:label="lab_ck0001027596_S000110367Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S000110367 Davidson Intermediate Taxable ETF C000281614</link:label>
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    <link:label id="lab_ck0001027596_ETFRisksMember_documentation_en-US" xlink:label="lab_ck0001027596_ETFRisksMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ETF Risks Member</link:label>
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    <link:label id="lab_ck0001027596_CorporateBondRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_CorporateBondRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Corporate Bond Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_CorporateBondRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_CorporateBondRiskMember"/>
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    <link:label id="lab_ck0001027596_ETFRisksCostsOfBuyingOrSellingSharesRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ETFRisksCostsOfBuyingOrSellingSharesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ETF Risks, Costs Of Buying Or Selling Shares Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_ETFRisksCostsOfBuyingOrSellingSharesRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_ETFRisksCostsOfBuyingOrSellingSharesRiskMember"/>
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    <link:label id="lab_ck0001027596_SectorEmphasisRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_SectorEmphasisRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_SectorEmphasisRiskMember"/>
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    <link:label id="lab_ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Risks Associated With Asset-Backed Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember" xlink:to="lab_ck0001027596_RisksAssociatedWithAssetBackedSecuritiesRiskMember" xlink:type="arc" order="1"/>
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    <link:label id="lab_ck0001027596_ETFRisksSharesMayTradeAtPricesOtherThanNAVRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ETFRisksSharesMayTradeAtPricesOtherThanNAVRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ETF Risks, Shares May Trade At Prices Other Than NAV Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_ETFRisksSharesMayTradeAtPricesOtherThanNAVRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_ETFRisksSharesMayTradeAtPricesOtherThanNAVRiskMember"/>
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    <link:label id="lab_ck0001027596_U.S.GovernmentSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_U.S.GovernmentSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">U.S. Government Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_U.S.GovernmentSecuritiesRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_U.S.GovernmentSecuritiesRiskMember"/>
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    <link:label id="lab_ck0001027596_EconomicAndMarketRiskMember_label_en-US" xlink:label="lab_ck0001027596_EconomicAndMarketRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Economic And Market Risk Member</link:label>
    <link:label id="lab_ck0001027596_EconomicAndMarketRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_EconomicAndMarketRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Economic And Market Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_EconomicAndMarketRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_EconomicAndMarketRiskMember"/>
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    <link:label id="lab_ck0001027596_C000281614Member_label_en-US" xlink:label="lab_ck0001027596_C000281614Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Davidson Intermediate Taxable ETF Class</link:label>
    <link:label id="lab_ck0001027596_C000281614Member_documentation_en-US" xlink:label="lab_ck0001027596_C000281614Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">S000110367 Davidson Intermediate Taxable ETF C000281614</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000281614Member" xlink:href="ck0001027596-20261028.xsd#ck0001027596_C000281614Member"/>
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    <link:label id="lab_ck0001027596_PrepaymentRisk1Member_label_en-US" xlink:label="lab_ck0001027596_PrepaymentRisk1Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepayment Risk 1 Member</link:label>
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    <link:label id="lab_ck0001027596_ETFRisksTradingRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ETFRisksTradingRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ETF Risks, Trading Risk Member</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_LiquidityRiskMember" xlink:href="ck0001027596-20261028.xsd#ck0001027596_LiquidityRiskMember"/>
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