I was having an issue where anything in the lowest price range was duplicated, so you see 2 of the same products side by side, I have a heavily modified store and think the cause of this issue is to do with a "inc VAT and EX Vat" mod i added, Only change this if you are also having this issue.

Find:

$select_str = "select distinct " . $select_column_list . " p.products_id, pd.products_name, p.products_price, p.products_tax_class_id, IF(s.status, s.specials_new_products_price, NULL) as specials_new_products_price, IF(s.status, s.specials_new_products_price, p.products_price) as final_price ";

if ( (DISPLAY_PRICE_WITH_TAX == 'true') && (tep_not_null($pfrom) || tep_not_null($pto)) ) {
$select_str .= ", SUM(tr.tax_rate) as tax_rate ";
}

Change to:

$select_str = "select distinct " . $select_column_list . " p.products_id, pd.products_name, p.products_price, p.products_tax_class_id, IF(s.status, s.specials_new_products_price, NULL) as specials_new_products_price, IF(s.status, s.specials_new_products_price, p.products_price) as final_price ";

if ( (DISPLAY_PRICE_WITH_TAX == 'false') && (tep_not_null($pfrom) || tep_not_null($pto)) ) {
$select_str .= ", SUM(tr.tax_rate) as tax_rate ";
}



//////Done!

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