Slow HSDPA Data Connection, Froyo 2.2

[dneill2006]

When I was using Android 2.1 on HSDPA I could get 1.5mbps

But now since using Froyo 2.2 I can only ever get a max of 0.5mbps no matter where I am.

I'm on O2, could it be the APN settings are wrong?

I'm using a custom ROM

Official 2.2, with: busybox, old A2SD+, OpenVPN (TUN), EXT4 support, 802.11N

But I have tried a few Froyo custom ROMs all with the same problem

Does anyone know the reason why I can't get faster than 0.5mbps on 2.2 while on 2.1 I could get 1.5mbps?

Thanks