The thing about XML::Simple is that it is sometimes just too simple (more e.g. here).

XML::LibXML + XPath solution:

use XML::LibXML;
my $dom = XML::LibXML->load_xml(location=>'test.xml');
my @nodes = $dom->findnodes('/Settings/Channels/Channel[@Voltage]');
print @nodes ? "Found it!\n" : "Didn't Find it!\n";

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In reply to Re: confirming key in xml? by Anonymous Monk
in thread confirming key in xml? by ccherri

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