Hi Dan,
You should enable Type-4(SD Stats on Time Slot Level) and Type-5(TCH Stats on Time slot Level) to check if the odd or the even timelot have greater no of drops on them if so then you have a OTS Issue.
As far as I know Alcatel has a hardware architecture that has different processors for odd and even TS and its placed such that one of the processor heats up and starts generating errors due to some faulty component. Its usually a batch of kown origin which can be traced and replaced.
The new batches have this issue fixed.