A couple of days ago we lost quite a number of channels from Freeview and have not been able to get them back by re-scanning. A bit of background info... We are in the ME19 postcode area and use the Bluebell Hill transmitter in Maidstone. We have had the same aerial setup for over 10 years. Aerial is located in the loft and was (iirc) labelled as a "wide band" aerial when purchased. This feeds into a 4 way SLx masthead amplifier which runs down to the living room and to 3 bedrooms. One of the bedrooms houses the SLx PSU and the masthead amplifier has the jumper set accordingly. Signal strength and quality levels are usually both at 100% for all channels. We had Sky TV for a long time, only cancelling it about 9 months ago. But this was in the living room only. We have always relied on Freeview in the bedrooms. Back in April we had a lot of drop out, such as pixelation, for a few days before then losing most channels. After a few days I purely by accident managed to fix the issue by replacing the aerial lead that ran between the PSU and the wall plate. There is no reason to believe that external forces would have affected the existing cable that had been in place for many years. But the replacement was shorter and thicker, looking like it would be better quality. In early July we lost some channels late at night and couldn't get them back until the next morning upon re-scanning. I wonder if this was related to the scheduled re-scan required for 17th July. Indeed, we did see the same behaviour upon the scheduled date. All was ok between rescans and since the last one... Until a couple of days ago. We lost a load of channels, with the same being apparent on all TVs in the house. The channels that we lost were those on C32, C34, C39+ & C46. No amount of rescanning on any TV is bringing the channels back. However, having a further play last night I found that if I either powered off the PSU for the masthead amplifier or removed it completely then I got almost all of the channels back on the TV in the bedroom that houses the PSU. The signal strength and quality levels were much lower than before (between 40% and 60%), but I didn't notice any drop out at all. However, rescanning the downstairs TV whilst the PSU was powered off resulted in even fewer channels. Whilst I got some of the previously missing SD channels back (such as BBC1 & BBC2), I lost many others and lost all HD channels. Now what I am thinking is that as the bedroom with the PSU is jumpered at the amplifier for the power feed, then this must be the only aerial point with a direct feed from the aerial when the PSU is powered off. Hence why this yields much better results with the PSU switched off. So the question really is, what is likely to be causing these problems? My first thought is that perhaps either the PSU or the masthead amplifier has developed a fault and I need to replace them. Would this be the most likely cause and fix? Alternatively, is it at all likely that with the recent changes that the signal is actually too strong (if there is such a thing) and that the amplifier should be replaced with a splitter? I can't see that it would be purely down to atmospheric conditions, else I'd have expected to see this behaviour in the past. Of course the latest channel loss does appear to have coincided with the sudden period of heavy rain. However, with the aerial and amplifier inside the loft I don't believe that this could have had an effect either. And I'm not aware of having a leak in the roof. Could anyone offer any suggestions or advice? Should I simply go the most obvious route of replacing the amp? If so, I don't seem to be able to find the same SLx kit, so any recommendations? Many thanks, Simon Update: So I believe that the masthead amplifier that I have is an SLx4M. I have found a scan of an old SLx product document from which I'd say that it is actually the SLx4M 27838R (I'll have to get up in the loft to check in order to be 100% certain). The document shows this as having a 12dB gain per split and confirms that there is no variable or switchable gain. I have found myself going back to the thought that perhaps the recent changes have resulted in a stronger signal which after the gain has been applied is too strong for the receivers. Is this realistic? If so, would I be best to try replacing the masthead amplifier with a different one that has variable gain, allowing me to reduce it from the current levels?