The VU+ Solo is over 10 years old, which in the world of computer electronics is old.
As to dropouts, it i usually either an issue with the cable connection to the sat (for example corrosion due to moisture), which you should be able to see as a drop of dB's. If during a dropout the menu is also gone, it might be a HDMI cable issue. It could also be a problem with the smartcard, it generates dropouts when it is overloaded. But this is probably unlikely on a single tuner box.
If with freeze you mean the entire box is unresponsive, do you see a rotating spinner image in the top-left corner when that happens? Is there a disk connected to the box, or a disk mounted over the network? Does it recover after a while, or does it stay frozen permanently?