Would this affect the thoughput?

yep,
for every uncorrected error a timeout and retransmission occurs,
1000/hr will certainly be more than noticeable.
time to check filters etc.

I believe it unlikely that the OP would notice that level of errors. There are 4000 frames per second so in the course of 4 hours 57,600,000 would have been received. Unless the OP was downloading continuously the bulk of those frames will be idle frames. 4032 out of 57,600,000 is an error rate of 0.007%.

eta: mixed up my frames, error reporting is over superframes (68 ADSL frames) of which there are 58.8 per second so 847,059 in four hours giving an error rate of 4032 out of 847,059 or 0.48%.

Edited by deleted (Wed 15-Jun-11 21:21:01)

It does however give suggestions on how to improve

cheers it looks like a throttling issue as I got a speed test of 9mb this evening!