Hi isaacj and welcome to beoworld,
your problem is that the Beogram 5005 doesn't have a RIAA phono preamp fitted and neither does the Beosound 2300 so you need to fit one between both units. The good news is that you hear some sound which suggests that the cartridge on your Beogram is good order and is the most expensive part to replace
. You can pick up a RIAA preamp from any decent electronics retailer but you may need a couple of phono/Din adaptor cables as most preamps have phono connections and your Beogram will have a 7 pin DIN outlet. Most adaptors are 5 pin DIN but pins 1&7 on your Beogram 5005 simply unscrew to allow this - these pins are for the datalink remote control and won't affect the sound but don't lose them as it is almost impossible to find replacements and you will need them if you ever decide to sell the Beogram at a later date. If this sounds a little confusing then Lee at LifeStyleAV in the UK can supply a good quality ready to use phono preamp KIT for exactly this application.
Another option would be to buy a beogram with RIAA already built in but these turntables tend to be very expensive but would plug & play directly via the AUX input. The models which have this are Beograms 6000 (quad) / 3500 / 4500 / 6500 & 7000 the latter 3 being the best cosmetic match to your Beosound although they ALL share the same basic chassis as your 5005 so an external preamp would probably be the cheapest if not the most elegant solution. Don't worry about losing the remote control facility by doing this as the AUX input of the Beosound 2300 doesn't facilitate this in any case.
Chris.
The use of metaphors should be avoided like the plague. They're like a red rag to a bull to me.