Just had a epoxy dipped solid tantalum capacitor fail in my Tektronix PG506. It gradually overheated, cracked, and started oozing molten metal, and it is not the first time this PG506 has done this. Last time I was watching it when it happened, and I changed all of the similar solid tantalum capacitors. Now I have more to change, and need to check the regulator circuits.
Tantalum capacitors might fail in this way when the power supply has current limiting.