I had your same issue using the poll plugin.
I had to modify the qa-include/qa-app-format.php at line 525 (q2a 1.6.2)
from :
if (@$options['whoview']) {
$fields['who']=qa_who_to_html($isbyuser, @$post['userid'], $usershtml, @$options['ipview'] ? @$post['createip'] : null, $microformats, $post['name']);
to :
if (@$options['whoview']) {
$fields['who']=qa_who_to_html($isbyuser, @$post['userid'], $usershtml, @$options['ipview'] ? @$post['createip'] : null, $microformats, @$post['name']);