Hi, I've been developing an application using CELT for some time and, for simplicity, have restricted frame sizes to powers of 2. During final testing I tested with a sound interface (the Phonic Firefly 302) whose ASIO drivers are very restictive in what they accept, and have about 6 allowable frame sizes < 512, a lot of which are odd numbers. However some are even numbered, so this should work. Unfortunately it doesn't and en exception is raised. Some investigation reveals the problem to be in the module kiss_fft.c, during allocation of storage for the FFT. The factorisation function kf_factor returns a failure if the frame size has a prime factor > 5. This results in the block which wasn't yet allocated being freed, and hence the exception. Given this restriction, their is no frame size that the both the driver and CELT will accept. I'd like to avoid the fancy footwork involved in having different frame sizes, if at all possible. My question is (a) is this the intended behaviour, or am I missing something? and (b)is there a way around this restriction? I've also tried to address this with Phonic, because this sort of behaviour of the driver is weird and is not a problem with the WDM drivers, but they're not answering.