I am now on my 8th BT TV box in total and 4th HD TV box.
A BT engineer will make a 3rd visit my home on Monday.
The signal strength on Freeview channels is 100% and 100% picture quality.
The last box worked fine from new for 25 days (box fitted BT engineer) and fine for a variable period of time from 2 hours to a couple days after a soft reset. Each time the TV box is replaced or factory (hard) reset all recorded programs are lost.
I have tried fitting a signal attenuator and reducing the signal strength to 95-98% but this only helped some channels. The poor channels the signal strength dropped to 85% but the quality dropped to 0-10%. Also the signal quality was fluctuating.
If this next visit by the engineer cannot resolve my issue I will forced to another system and cancel my telephone, broadband and tv, and go with a local supplier that can properly support their product.
This because I travel abroad on business and rely on the BT box to record programmes whilst I am away. I then like to watch the programmes on my return but find the recordings are sometimes pixelated and unwatchable.
You really need a variable attenuator (0-20dB) and ramp it up to reduce the signal strength down to 90% or maybe less. Your 95-98% is still too high and can easily be causing the low & fluctuating signal strength on other channels as the tuners are being overloaded.
Started to get similar but a temporary aerial cable would work - eventually found water getting in to the connection at the aeriel end.
One other thing to look at is the run of aerial cable alongside the HDMI and power cables etc. Try putting some separation between the two and not have the cables running parallel with each other for any distance.
The BT engineer came today but did not resolve the issue.
After I had explained what I had done with a signal attenuator, he connected a signal monitoring meter and agreed the signal was very strong.
The BT engineer stated the attenuator I had previously used was not the best solution because it was 20db and to strong.
The BT engineer suggested that I fit a 6 or 8db attenuator.
He stated that BT engineers are not now issued with signal attenuators. He had previously a stock of attenuators but not now.
He suggested that if he obtained an attenuator, he would drop one off at my home. However, I do not believe this will happen.
Therefore, I have ordered a 6db in-line attenuator from Amazon, which should arrive later this week.
With the 0-20 attenuator and the signal restricted to 95%, some channels drop to 80% signal but 0-10% quality.
The BT engineer advised using a fixed 6-8db attenuator.