Bought a new set of the exact brand and gauge of strings that are were on my 1527, La Bella HRS 9-64's. And I cannot get the low B to intonate. Adjusted the saddle 6 or 7 times and it's just way off no matter how I adjust it forward or backward. Could it be a bad string? I've never had an issue intonating this guitar in the several years I've owned it, and never had a string sound this off after several adjustments. Any ideas?