Low Testosterone!!!

Any one out there have a husband or SO with low testoserone levels? My husband does, we have been TTC for a year and I am sure we are both healthy enough to concieve. It is very frustrating that he is not really in the mood enough to even try to concieve. He takes a shot once a week but we still go for 2 or 3 weeks in between sex. Anyone have any advise for this????