How to prevent subwoofer from going to the stand by mode

The blue indicator light on the front of the subwoofer will ONLY illuminate when a low frequency sound is being passed to the speaker. The light may not illuminate in the presence of normal dialog or high frequency music since these sounds would not be passed to the subwoofer for processing. If you wish to have your subwoofer further evaluated by an authorized Onkyo service center- Here is the information on how to obtain warranty service for your product and the nearest service center locations to drop off/send your product for warranty service.

To obtain warranty service, take or ship your Onkyo product to an Onkyo Authorized Service Center, together with a note describing your complaint and your copy of the dated purchase receipt. Please also include the attached and completed Customer Warranty Service Documentation form attached to this email. Please input your name, address, telephone number, and serial number of the unit. You need to provide, at your expense, shipment of your Onkyo product to an authorized Service Center. Onkyo will pay all return shipping charges for Onkyo products that have been serviced under this warranty. This Warranty is valid two years from date of purchase and is valid only within the territory of the United States of America. To be covered by this warranty the Onkyo product concerned must have been purchased directly from Onkyo or an Onkyo Authorized Dealer and the person seeking warranty service must reside in one of the states of the United States of America or in the District of Columbia. This warranty extends only to the original purchaser and cannot be transferred to anyone.

According to customers on the Amazon website there is no override option to prevent it switching off.