I believe I have identified a problem with the Twin handling of weak signals. I have resolved my problems through an aerial upgrade to the DAT75, which I highly recommend, but if anyone else is having reception problems in a weak signal area, and find that a system reset improves the problem, then I suggest they contact Pace.
I today send this to their customer support:
Hi,
I believe I have now identified the problem, and although I have resolved it for myself through an aerial upgrade, I still believe there to be a fault in the Twin, so please read on.
It seems as if the Twin is unable to properly lock back on to a signal (even a strong one), after it has had a weak signal for some time. I have come to this conclusion for the following reasons:
1. For me, BBC Mux1 was giving a signal strength of about 37%, whilst other Muxes were around 45%;
2. I very frequently experienced reception problems, with the BitError rate meter showing errors - occasionally I would lose the signal all together;
3. I could temporarily fix the problem by resetting the unit, and re-tuning to the signal. I could do this even just after the fault at (2) seemed very bad with no signal received at all. The Twin would then behave itself for some hours;
4. I eventually resorted to an aerial upgrade, but despite then getting a signal strength of 67% on Mux1 and 75% on others, the problem seemed to persist - I continued to clock up BitErrors and to have reception problems;
5. I again reset the Twin, and it has been fine since.
So it seems that despite upgrading my aerial, the Twin was unable to lock back on to that now strong signal, as it had previously drifted off whilst using the old aerial.
Whilst I have fixed the problem myself, it would seem that Pace could improve the way the Twin handles weak signals (enabling it to lock back on, without having to reset), and so improve reception (most of the time) for users in weak reception areas.