The maximum speed for the interrupt transfer for USB 2.0 full speed is 64kbytes/s. LPC2148 is used in device side. Is there a possibility of increasing the interrupt transfer speed by increasing the packet size. In that case generic device class wont support the device. Is there any possibility of moving to custom hid driver
can you make the oscilator jump fater?
No. There are 1000 frames / second, i.e. one every millisecond - and with a very, very strict requirement on allowed jitter. Change the oscillator frequency, and you will no longer have compatible USB communcation.