As an Inspector for a Manufacturer of Specialized Electronic Instruments

As an inspector for a manufacturer of specialized electronic instruments, you head up the quality assurance program at one of the firm's manufacturing plants. In recent days, it has come to your attention that a large order involving several hundred expensive instruments for an important customer does not meet all the required specifications. Specifically, the circuit which has been designed by your firm to warn the user of possible malfunction does not appear to work consistently. The firm's engineers say that the problem should have no significant results for the customer, as it does not affect the functionality of the instrument in any way. Moreover, the engineers indicate that it is a high priority for them to find an answer to the mysterious behavior of the circuit, and they will develop a fix as soon as possible, and make sure the customer is provided the fix, probably as part of a routine update or maintenance. The marketing V.P. indicates that the customer wants these instruments urgently, and that no quality assurance issues will get in the way.
The quality assurance head knows that the order is very important to the firm, as the firm has faced declining revenues in several recent months. Also, while the intentions of the engineers are likely to be sincere, the quality assurance head knows that they are very busy with current and new products, and are unlikely to have the time to deal with this problem in a timely manner.
Required:
What are the ethical issues involved in the case for the quality assurance head? What steps would you suggest be taken?