From Forum Nokia Wiki

With respect to the Active object framework in Symbian OS, Stray signal is a panic which is defined as E32USER-CBase 46.

There are following cases when stray signal may occur:

• CActiveScheduler::Add() was not called when the active object was constructed (it cause E32USER-CBase 49).
• SetActive() was not called following the submission of a request to the asynchronous service provider.
• The asynchronous service provider completed the TRequestStatus of an active object more than once – either because of "when an already-completed request is canceled" or "more than one request was submitted simultaneously on the same active object."