A few things are noteworthy.
Roughly where are you located within the county and what site were you holding onto for the test? The system should sound similar or better than what you hear on the VHF patch as it is just rebroadcasting the audio exactly as it was received by the system. Something you can do is to hold onto TG 1053 only and let it continue to cycle through sites to figure out which site works out best for you. If you were trying to do a site hold on Douglas County North Simulcast, Douglas County South Simulcast, Silver Heights (absorbed by Douglas County North Simulcast), or West Creek (adsorbed by Douglas County South Simulcast), then the broken audio could be a sign of
simulcast distortion. That is unfortunate as this is a known limitation of the BCD436HP, however you are free to try one of the many suggestions on the linked page. You might potentially have greater success using non-simulcast sites like Smoky Hill, Conifer Mountain, Franktown, and/or Silo to try to monitor TG 1053 as they usually have superior decode performance over a simulcast site.
You will probably want to update your scanner's database using a computer when you get a chance. It sounds like your scanner has a very old version of the database (pre-2016) as Silver Heights has not been a listed site in the database for years. Some things have changed over the years so you might have old site data with old control channels.
It sounds like you are using location based scanning which could mean that the scanner is trying to check too many sites. The Denver Metro area can be great for monitoring a wide range of talkgroups if you know exactly what you are doing, but it can also be challenging to focus in on a specific area if you are new. You can usually receive a lot of sites from very far away, but that is a problem when only a few specific sites nearby has the talkgroups you want to listen to locally. If you use the
Set Your Location feature, you will want to make sure your range is set to 0.0 miles to minimize the number of sites your scanner is trying to check. The scanner will only stop on that talkgroup if the specific site it is currently checking has that talkgroup on it and it can take up to a second for it to check each individual site. If the site does not have that talkgroup, it will remain silent as it checks all the sites it can receive, then it will check your conventional frequencies before returning to the system to check it from the beginning. If a majority of the sites being scanned does not carry TG 1053, then that could be why it seems like you only ever hear it on the VHF patch frequency since it has a higher chance of becoming active while your scanner was idly checking other sites.
You may want to considering learning more about programming your own Favorites Lists and Quick Keys using software as it will allow you to have great selectivity over things to monitor. You can assign Quick Keys to Departments and Sites which will let you choose exactly what you want to monitor and which sites you use to monitor.
