Hybrid Debt/Capital Instruments have features which include those of pure capital as well as pure debt instruments. The exact features that they possess is decided when they are issued.
In general hybrid debt/capital instruments are fully paid up. They are not secured and subordinated to pure equity instruments.
If a holder of these instruments is making losses the issuer is not obliged to liquidate them for the holder and the holder has to accept the losses made.
Also, though there is a higher priority given to holders of these instruments when interest is being paid, the issuer retains the right to defer payments if that would be in favor of profitability of the firm.